Merge ../Marian

scripts/train_test_model_multi.py

@@ -3,6 +3,7 @@
 import sys
 import os
 import numpy as np
+import time
 from keras.datasets import mnist
 from keras.utils import np_utils
 from keras.models import Sequential
@@ -15,7 +16,11 @@ def softmax(x):
 
 def baseline_model(pixels_count, classes_count):
     model = Sequential()
-    model.add(Dense(100, input_dim=pixels_count, init='normal', activation='tanh'))
+    model.add(Dense(2000, input_dim=pixels_count, init='normal', activation='tanh'))
+    model.add(Dense(2000, init='normal', activation='tanh'))
+    model.add(Dense(2000, init='normal', activation='tanh'))
+    model.add(Dense(2000, init='normal', activation='tanh'))
+    model.add(Dense(2000, init='normal', activation='tanh'))
     model.add(Dense(classes_count, input_dim=100, init='normal', activation='softmax'))
     model.compile(loss='categorical_crossentropy', optimizer='adam', metrics=['accuracy'])
     return model
@@ -52,21 +57,24 @@ if __name__ == "__main__":
     # Build the model
     model = baseline_model(pixels_count, classes_count)
     # Fit the model
-    model.fit(X_train, y_train, validation_data=(X_test, y_test), nb_epoch=10, batch_size=200, verbose=2)
+    
+    start = time.time();
+    model.fit(X_train, y_train, nb_epoch=10, batch_size=200, verbose=2)
+    print "Time elapsed", time.time() - start, "s"
     # Final evaluation of the model
     scores = model.evaluate(X_test, y_test, verbose=0)
-    print("Baseline Error: %.2f%%" % (100-scores[1]*100))
+    print("Accuracy: %.2f%%" % (scores[1] * 100))
 
     ### Weight and bias matrixes - we extract them from the model
     
     # weights_ones = np.ones((pixels_count, classes_count))
     # print weights_ones.shape
 
-    weights1, bias1, weights2, bias2 = model.get_weights()
+    #weights1, bias1, weights2, bias2 = model.get_weights()
     ### Save model to npz files
-    if not os.path.exists("test_model_multi"):
-        os.makedirs("test_model_multi")
+    #if not os.path.exists("test_model_multi"):
+    #    os.makedirs("test_model_multi")
     # np.savez("test_model_multi/model", *model)
-    np.savez("test_model_multi/model", weights1 = weights1, bias1 = bias1, weights2 = weights2, bias2 = bias2)
+    #np.savez("test_model_multi/model", weights1 = weights1, bias1 = bias1, weights2 = weights2, bias2 = bias2)
 
-    print "Model saved! Check test_model_multi directory"
+    #print "Model saved! Check test_model_multi directory"

src/CMakeLists.txt

@@ -21,30 +21,25 @@ cuda_add_executable(
 target_link_libraries(marian marian_lib)
 
 cuda_add_executable(
-  train_mnist
-  train_mnist.cu
+  mnist_benchmark
+  mnist_benchmark.cu
 )
 
-target_link_libraries(train_mnist marian_lib)
-
-cuda_add_executable(
-  validate_mnist
-  validate_mnist.cu
-)
 cuda_add_executable(
   validate_mnist_batch
   validate_mnist_batch.cu
 )
+
 cuda_add_executable(
   validate_encoder_decoder
   validate_encoder_decoder.cu
 )
 
-target_link_libraries(validate_mnist marian_lib)
+target_link_libraries(mnist_benchmark marian_lib)
 target_link_libraries(validate_mnist_batch marian_lib)
 target_link_libraries(validate_encoder_decoder marian_lib)
 
-foreach(exec marian train_mnist validate_mnist validate_mnist_batch validate_encoder_decoder)
+foreach(exec marian mnist_benchmark validate_mnist_batch validate_encoder_decoder)
   target_link_libraries(${exec} ${EXT_LIBS} cuda cudnn)
   cuda_add_cublas_to_target(${exec})
   set_target_properties(${exec} PROPERTIES RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}")

src/mnist_benchmark.cu

@@ -0,0 +1,164 @@
+#include <algorithm>
+#include <chrono>
+#include <boost/timer/timer.hpp>
+
+#include "marian.h"
+#include "mnist.h"
+#include "npz_converter.h"
+#include "optimizers.h"
+
+using namespace marian;
+using namespace keywords;
+
+const size_t IMAGE_SIZE = 784;
+const size_t LABEL_SIZE = 10;
+int BATCH_SIZE = 200;
+
+ExpressionGraph build_graph(const std::vector<int>& dims) {
+  std::cerr << "Building model... ";
+  boost::timer::cpu_timer timer;
+    
+  ExpressionGraph g;
+  auto x = named(g.input(shape={whatevs, IMAGE_SIZE}), "x");
+  auto y = named(g.input(shape={whatevs, LABEL_SIZE}), "y");
+  
+  std::vector<Expr> layers, weights, biases;
+  for(int i = 0; i < dims.size()-1; ++i) {
+    int in = dims[i];
+    int out = dims[i+1];
+      
+    if(i == 0) {
+      layers.emplace_back(x);
+    }
+    else {
+      layers.emplace_back(tanh(dot(layers.back(), weights.back())) + biases.back());
+    }
+    
+    weights.emplace_back(
+      g.param(shape={in, out},
+            init=normal()));
+    biases.emplace_back(
+      g.param(shape={1, out},
+            init=normal()));
+
+  }
+  
+  auto probs = named(
+    softmax(dot(layers.back(), weights.back()) + biases.back()),
+    "probs"
+  );
+  
+  auto cost = -mean(sum(y * log(probs), axis=1), axis=0);
+  auto costreg = named(
+    cost, "cost"
+  );
+
+  std::cerr << timer.format(5, "%ws") << std::endl;
+  return g;
+}
+
+void shuffle(std::vector<float>& x, std::vector<float>& y, size_t dimx, size_t dimy) {
+  std::srand(std::time(0));
+  std::vector<size_t> ind;
+  for(size_t i = 0; i < x.size() / dimx; ++i) {
+    ind.push_back(i);
+  }
+  
+  std::random_shuffle(ind.begin(), ind.end());
+  
+  std::vector<float> xShuffled(x.size());
+  std::vector<float> yShuffled(y.size());
+  
+  int j = 0;
+  for(auto i : ind) {
+    std::copy(x.begin() + j * dimx, x.begin() + j * dimx + dimx, xShuffled.begin() + i * dimx);
+    std::copy(y.begin() + j * dimy, y.begin() + j * dimy + dimy, yShuffled.begin() + i * dimy);
+    j++;
+  }
+  
+  x = xShuffled;
+  y = yShuffled;
+  
+}
+
+int main(int argc, char** argv) {
+
+  int trainRows, testRows;
+  
+  std::cerr << "Loading train set...";
+  std::vector<float> trainImages = datasets::mnist::ReadImages("../examples/mnist/train-images-idx3-ubyte", trainRows, IMAGE_SIZE);
+  std::vector<float> trainLabels = datasets::mnist::ReadLabels("../examples/mnist/train-labels-idx1-ubyte", trainRows, LABEL_SIZE);
+  std::cerr << "Done." << std::endl;
+  
+  std::cerr << "Loading test set...";
+  std::vector<float> testImages = datasets::mnist::ReadImages("../examples/mnist/t10k-images-idx3-ubyte", testRows, IMAGE_SIZE);
+  std::vector<float> testLabels = datasets::mnist::ReadLabels("../examples/mnist/t10k-labels-idx1-ubyte", testRows, LABEL_SIZE);
+  std::cerr << "Done." << std::endl;
+
+  ExpressionGraph g = build_graph({IMAGE_SIZE, 2000, 2000, 2000, 2000, 2000, LABEL_SIZE});
+  
+  Tensor xt({BATCH_SIZE, IMAGE_SIZE});
+  Tensor yt({BATCH_SIZE, LABEL_SIZE});
+
+  
+  boost::timer::cpu_timer total;
+  Adam opt;
+  for(int i = 1; i <= 10; ++i) {
+    boost::timer::cpu_timer timer;
+    shuffle(trainImages, trainLabels, IMAGE_SIZE, LABEL_SIZE);
+    float cost = 0;
+    for(int j = 0; j < trainRows / BATCH_SIZE; j++) {
+      size_t xBatch = IMAGE_SIZE * BATCH_SIZE;
+      auto xbegin = trainImages.begin() + j * xBatch;
+      auto xend = xbegin + xBatch;
+      xt.set(xbegin, xend);
+      
+      size_t yBatch = LABEL_SIZE * BATCH_SIZE;
+      auto ybegin = trainLabels.begin() + j * yBatch;
+      auto yend = ybegin + yBatch;
+      yt.set(ybegin, yend);
+      
+      g["x"] = xt;
+      g["y"] = yt;
+      
+      opt(g, BATCH_SIZE);
+      cost += g["cost"].val()[0];
+    }
+    std::cerr << "Epoch: " << i << " - Cost: " << cost / trainRows * BATCH_SIZE << " - " << timer.format(3, "%ws") << std::endl;
+  }
+  std::cerr << "Total: " << total.format(3, "%ws") << std::endl;
+
+  std::vector<float> results;  
+  for(int j = 0; j < testRows / BATCH_SIZE; j++) {
+    size_t xBatch = IMAGE_SIZE * BATCH_SIZE;
+    auto xbegin = testImages.begin() + j * xBatch;
+    auto xend = xbegin + xBatch;
+    xt.set(xbegin, xend);
+    yt.set(0);  
+      
+    g["x"] = xt;
+    g["y"] = yt;
+    
+    g.forward(BATCH_SIZE);
+    
+    std::vector<float> bResults;
+    bResults << g["probs"].val();
+    results.insert(results.end(), bResults.begin(), bResults.end());
+  }
+  
+  size_t acc = 0;
+  for (size_t i = 0; i < testLabels.size(); i += LABEL_SIZE) {
+    size_t correct = 0;
+    size_t proposed = 0;
+    for (size_t j = 0; j < LABEL_SIZE; ++j) {
+      if (testLabels[i + j])
+        correct = j;
+      if (results[i + j] > results[i + proposed])
+        proposed = j;
+    }
+    acc += (correct == proposed);
+  }
+  std::cerr << "Accuracy: " << float(acc) / testRows << std::endl;
+  
+  return 0;
+}

src/node_operators.h

@@ -114,7 +114,7 @@ struct LogitNodeOp : public UnaryNodeOp {
   virtual std::string graphviz() {
     std::stringstream ss;
     ss << "\"" << this << "\" [shape=\"box\", label=\"logit\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
-    ss << "\"" << &*a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
+    ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
     return ss.str();
   };
 
@@ -138,7 +138,7 @@ struct TanhNodeOp : public UnaryNodeOp {
   virtual std::string graphviz() {
     std::stringstream ss;
     ss << "\"" << this << "\" [shape=\"box\", label=\"tanh\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
-    ss << "\"" << &*a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
+    ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
     return ss.str();
   };
 
@@ -180,7 +180,7 @@ struct SoftmaxNodeOp : public UnaryNodeOp {
   virtual std::string graphviz() {
     std::stringstream ss;
     ss << "\"" << this << "\" [shape=\"box\", label=\"softmax\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
-    ss << "\"" << &*a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
+    ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
     return ss.str();
   };
 
@@ -209,7 +209,7 @@ struct ArgmaxNodeOp : public UnaryNodeOp {
   virtual std::string graphviz() {
     std::stringstream ss;
     ss << "\"" << this << "\" [shape=\"box\", label=\"argmax\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
-    ss << "\"" << &*a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
+    ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
     return ss.str();
   };
 
@@ -232,7 +232,7 @@ struct LogNodeOp : public UnaryNodeOp {
   virtual std::string graphviz() {
     std::stringstream ss;
     ss << "\"" << this << "\" [shape=\"box\", label=\"log\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
-    ss << "\"" << &*a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
+    ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
     return ss.str();
   };
 
@@ -255,7 +255,7 @@ struct ExpNodeOp : public UnaryNodeOp {
   virtual std::string graphviz() {
     std::stringstream ss;
     ss << "\"" << this << "\" [shape=\"box\", label=\"exp\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
-    ss << "\"" << &*a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
+    ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
     return ss.str();
   };
 
@@ -277,7 +277,7 @@ struct NegNodeOp : public UnaryNodeOp {
   virtual std::string graphviz() {
     std::stringstream ss;
     ss << "\"" << this << "\" [shape=\"box\", label=\"-\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
-    ss << "\"" << &*a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
+    ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
     return ss.str();
   };
 
@@ -330,8 +330,8 @@ struct DotNodeOp : public BinaryNodeOp {
   virtual std::string graphviz() {
     std::stringstream ss;
     ss << "\"" << this << "\" [shape=\"box\", label=\"×\", style=\"filled\", fillcolor=\"orange\"]" << std::endl;
-    ss << "\"" << &*a_ << "\" -> \"" << this << "\"" << std::endl;
-    ss << "\"" << &*b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
+    ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
+    ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
     return ss.str();
   };
 
@@ -357,8 +357,8 @@ struct PlusNodeOp : public BinaryNodeOp {
   virtual std::string graphviz() {
     std::stringstream ss;
     ss << "\"" << this << "\" [shape=\"box\", label=\"+\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
-    ss << "\"" << &*a_ << "\" -> \"" << this << "\"" << std::endl;
-    ss << "\"" << &*b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
+    ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
+    ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
     return ss.str();
   };
 
@@ -384,8 +384,8 @@ struct MinusNodeOp : public BinaryNodeOp {
   virtual std::string graphviz() {
     std::stringstream ss;
     ss << "\"" << this << "\" [shape=\"box\", label=\"-\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
-    ss << "\"" << &*a_ << "\" -> \"" << this << "\"" << std::endl;
-    ss << "\"" << &*b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
+    ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
+    ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
     return ss.str();
   };
 
@@ -411,8 +411,8 @@ struct MultNodeOp : public BinaryNodeOp {
   virtual std::string graphviz() {
     std::stringstream ss;
     ss << "\"" << this << "\" [shape=\"box\", label=\"•\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
-    ss << "\"" << &*a_ << "\" -> \"" << this << "\"" << std::endl;
-    ss << "\"" << &*b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
+    ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
+    ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
     return ss.str();
   };
 

src/optimizers.h

@@ -6,9 +6,15 @@
 
 namespace marian {
 
+// @TODO: modify computation graph to group all paramters in single matrix object.
+// This will allow to perform a single large SGD update per batch. Currently there
+// are as many updates as different paramters.
+
+// @TODO: Implement Element(...) with multiple functors for compacting of calls.
+
 class Sgd {
   public:
-    Sgd(float eta=0.001) : eta_(eta) {}
+    Sgd(float eta=0.01) : eta_(eta) {}
     
     void operator()(ExpressionGraph& graph, int batchSize) {
       graph.backprop(batchSize);
@@ -25,7 +31,7 @@ class Sgd {
 // @TODO: Add serialization for historic gradients and parameters
 class Adagrad {
   public:
-    Adagrad(float eta=0.001, float eps=10e-8)
+    Adagrad(float eta=0.01, float eps=1e-8)
     : eta_(eta), eps_(eps) {}
     
     void operator()(ExpressionGraph& graph, int batchSize) {
@@ -55,7 +61,7 @@ class Adagrad {
 // https://arxiv.org/pdf/1412.6980v8.pdf
 class Adam {
   public:
-    Adam(float eta=0.001, float beta1=0.999, float beta2=0.999, float eps=10e-8)
+    Adam(float eta=0.001, float beta1=0.9, float beta2=0.999, float eps=1e-8)
     : eta_(eta), beta1_(beta1), beta2_(beta2), eps_(eps), t_(0) {}
     
     void operator()(ExpressionGraph& graph, int batchSize) {

src/param_initializers.h

@@ -33,13 +33,13 @@ void distribution(Tensor t, float a, float b) {
   t << vals;
 }
 
-std::function<void(Tensor)> normal(float mean = 0.0, float std = 0.1) {
+std::function<void(Tensor)> normal(float mean = 0.0, float std = 0.05) {
   return [mean, std](Tensor t) {
     distribution<std::normal_distribution<float>>(t, mean, std);
   }; 
 }
 
-std::function<void(Tensor)> uniform(float a = 0.0, float b = 0.1) {
+std::function<void(Tensor)> uniform(float a = 0.0, float b = 0.05) {
   return [a, b](Tensor t) {
     distribution<std::uniform_real_distribution<float>>(t, a, b);
   };  

src/tensor_operators.cu

@@ -4,6 +4,14 @@ using namespace std;
 
 namespace marian {
 
+// @TODO: handle this better, maybe per thread?
+static cublasHandle_t create_handle() {
+  cublasHandle_t cublasHandle;
+  cublasCreate(&cublasHandle);
+  return cublasHandle;
+}
+cublasHandle_t cublasHandle = create_handle();
+
 __global__ void gSubtractMean(float* out, float* weights,
                               size_t rows, size_t cols) {
   for(int bid = 0; bid < rows; bid += gridDim.x) {
@@ -212,10 +220,7 @@ Tensor Prod(cublasHandle_t handle, Tensor C, const Tensor A, const Tensor B,
 Tensor Prod(Tensor C, const Tensor A, const Tensor B,
              bool transA, bool transB, Float beta) {
 
-  cublasHandle_t cublasHandle;
-  cublasCreate(&cublasHandle);  
   Tensor temp = Prod(cublasHandle, C, A, B, transA, transB, beta);
-  cublasDestroy(cublasHandle);
   return temp;
 }
 

src/train_mnist.cu

@@ -1,34 +0,0 @@
-
-#include "marian.h"
-#include "mnist.h"
-#include "optimizers.h"
-
-int main(int argc, char** argv) {
-  const size_t IMAGE_SIZE = 784;
-  const size_t LABEL_SIZE = 10;
-  int numofdata;
-
-  std::vector<float> trainImages = datasets::mnist::ReadImages("../examples/mnist/t10k-images-idx3-ubyte", numofdata, IMAGE_SIZE);
-  std::vector<float> trainLabels = datasets::mnist::ReadLabels("../examples/mnist/t10k-labels-idx1-ubyte", numofdata, LABEL_SIZE);
-
-  using namespace marian;
-  using namespace keywords;
-
-  ExpressionGraph g;
-  
-  Expr x = named(g.input(shape={whatevs, IMAGE_SIZE}), "x");
-  Expr y = named(g.input(shape={whatevs, LABEL_SIZE}), "y");
-
-  Expr w = named(g.param(shape={IMAGE_SIZE, LABEL_SIZE}), "w");
-  Expr b = named(g.param(shape={1, LABEL_SIZE}), "b");
-
-  auto scores = dot(x, w) + b;
-  auto lr = softmax(scores);
-  auto cost = named(-mean(sum(y * log(lr), axis=1), axis=0), "cost");
-  std::cerr << "lr=" << lr.Debug() << std::endl;
-
-  Adagrad opt;
-  opt(g, 300);
-  
-  return 0;
-}

src/validate_mnist.cu

@@ -1,90 +0,0 @@
-
-#include "marian.h"
-#include "mnist.h"
-#include "npz_converter.h"
-#include "optimizers.h"
-
-using namespace marian;
-using namespace keywords;
-
-const size_t IMAGE_SIZE = 784;
-const size_t LABEL_SIZE = 10;
-int BATCH_SIZE = 10000;
-
-ExpressionGraph build_graph() {
-  std::cerr << "Loading model params...";
-  NpzConverter converter("../scripts/test_model_single/model.npz");
-
-  std::vector<float> wData, bData;
-  Shape wShape, bShape;
-  converter.Load("weights", wData, wShape);
-  converter.Load("bias", bData, bShape);
-  std::cerr << "Done." << std::endl;
-
-  std::cerr << "Building model...";
-  
-  ExpressionGraph g;
-  auto x = named(g.input(shape={whatevs, IMAGE_SIZE}), "x");
-  auto y = named(g.input(shape={whatevs, LABEL_SIZE}), "y");
-  
-  auto w = named(g.param(shape={IMAGE_SIZE, LABEL_SIZE},
-                         init=from_vector(wData)), "w");
-  auto b = named(g.param(shape={1, LABEL_SIZE},
-                         init=from_vector(bData)), "b");
-  
-                         
-  auto probs = named(
-    softmax(dot(x, w) + b),
-    "probs"
-  );
-  
-  auto cost = named(
-    -mean(sum(y * log(probs), axis=1), axis=0),
-    "cost"
-  );
-  
-  std::cerr << "Done." << std::endl;
-  return g;
-}
-
-int main(int argc, char** argv) {
-
-  std::cerr << "Loading test set...";
-  std::vector<float> testImages = datasets::mnist::ReadImages("../examples/mnist/t10k-images-idx3-ubyte", BATCH_SIZE, IMAGE_SIZE);
-  std::vector<float> testLabels = datasets::mnist::ReadLabels("../examples/mnist/t10k-labels-idx1-ubyte", BATCH_SIZE, LABEL_SIZE);
-  std::cerr << "Done." << std::endl;
-
-  ExpressionGraph g = build_graph();
-  
-  Tensor xt({BATCH_SIZE, IMAGE_SIZE});
-  Tensor yt({BATCH_SIZE, LABEL_SIZE});
-  
-  g["x"] = (xt << testImages);
-  g["y"] = (yt << testLabels);
-  
-  Adam opt;
-  for(size_t j = 0; j < 20; ++j) {
-    for(size_t i = 0; i < 60; ++i) {
-      opt(g, BATCH_SIZE);
-    }
-    std::cerr << g["cost"].val()[0] << std::endl;
-  }
-  
-  //std::cout << g.graphviz() << std::endl;
-  
-  std::vector<float> results;
-  results << g["probs"].val();
-  
-  size_t acc = 0;
-  for (size_t i = 0; i < testLabels.size(); i += LABEL_SIZE) {
-    size_t correct = 0;
-    size_t proposed = 0;
-    for (size_t j = 0; j < LABEL_SIZE; ++j) {
-      if (testLabels[i+j]) correct = j;
-      if (results[i + j] > results[i + proposed]) proposed = j;
-    }
-    acc += (correct == proposed);
-  }
-  std::cerr << "Cost: " << g["cost"].val()[0] <<  " - Accuracy: " << float(acc) / BATCH_SIZE << std::endl;
-  return 0;
-}