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Remove bad examples, reword places.
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@ -20,7 +20,7 @@ memory management and C will take you as far as you need to go.
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Multi-line comments look like this. They work in C89 as well.
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*/
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// Constants: #define <keyword> (no semicolon at end)
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// Constants: #define <keyword>
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#define DAYS_IN_YEAR 365
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//enumeration constants are also ways to declare constants.
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@ -38,7 +38,7 @@ enum days {SUN = 1, MON, TUE, WED, THU, FRI, SAT};
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// Declare function signatures in advance in a .h file, or at the top of
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// your .c file.
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void function_1(char s[]);
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void function_1(char c);
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int function_2(void);
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// Must declare a 'function prototype' before main() when functions occur after
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@ -84,8 +84,8 @@ int main() {
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unsigned long long ux_long_long;
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// chars inside single quotes are integers in machine's character set.
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'0' //==> 48 on the ASCII character set.
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'A' //==> 65 on the ASCII character set.
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'0' // => 48 in the ASCII character set.
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'A' // => 65 in the ASCII character set.
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// sizeof(T) gives you the size of a variable with type T in bytes
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// sizeof(obj) yields the size of the expression (variable, literal, etc.).
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@ -154,16 +154,16 @@ int main() {
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{6, 7, 8, 9, 0}
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}
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//access elements:
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int array_int = multi_array[0][2]; //=> 3
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int array_int = multi_array[0][2]; // => 3
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///////////////////////////////////////
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// Operators
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///////////////////////////////////////
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int i1 = 1, i2 = 2; // Shorthand for multiple declaration
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// Shorthands for multiple declarations:
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int i1 = 1, i2 = 2;
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float f1 = 1.0, f2 = 2.0;
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//more shorthands:
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int a, b, c;
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a = b = c = 0;
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@ -215,9 +215,9 @@ int main() {
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//Increment and decrement operators:
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char *s = "iLoveC"
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int j = 0;
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s[j++]; // => "i" Returns value of j to s THEN increments value of j.
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s[j++]; // => "i". Returns the j-th item of s THEN increments value of j.
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j = 0;
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s[++j]; // => "L" Increments value of j THEN returns value of j to s.
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s[++j]; // => "L". Increments value of j THEN returns j-th value of s.
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// same with j-- and --j
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// Bitwise operators!
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@ -271,7 +271,7 @@ int main() {
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printf("\n");
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// *****NOTES*****:
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// Loops MUST always have a body. If no body is needed, do:
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// Loops and Functions MUST have a body. If no body is needed:
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int i;
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for (i = 0; i <= 5; i++) {
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; // use semicolon to act as the body (null statement)
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@ -429,12 +429,12 @@ int add_two_ints(int x1, int x2)
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}
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/*
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Functions are call by value. So when a function is called, the arguments passed
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to the function are copies of original arguments (except arrays). Anything you
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do to your arguments do not change the value of the actual argument where the
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function was called.
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Functions are call by value. When a function is called, the arguments passed to
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the function are copies of the original arguments (except arrays). Anything you
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do to the arguments in the function do not change the value of the original
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argument where the function was called.
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You can use pointers if you need to edit the original argument values.
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Use pointers if you need to edit the original argument values.
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Example: in-place string reversal
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*/
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@ -452,19 +452,6 @@ void str_reverse(char *str_in)
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}
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}
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/////////////////////////////////////
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// Built in functions:
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/////////////////////////////////////
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// from: #include <stdio.h>
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// ** getchar() **
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// int c = getchar(); //reads character from input.
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// If input = hi, 'h' is returned then next call, 'i' returned.
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while ((c = getchar()) != EOF) { // EOF constant "end of file".
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// Linux: CTRL+D, Windows: CTRL+X
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// must have () around getchar() as != is run before =.
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putchar(c); //prints character (without newline at end)
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}
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//if referring to external variables outside function, must use extern keyword.
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int i = 0;
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void testFunc() {
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