Syntax Station

int myInt = 101;                 // Integer
float myFloat = 45.81;           // Float
char letter = 'a';               // Character
char message[] = "Hello World!"; // String (Array of characters)

// C99 adds boolean type with <stdbool.h>
// bool positive = true;

// Comment on a single line
/*
   Block comments
   Everything in here will be
   treated as a comment
*/

int foo = 5;
foo++;

int bar = 10;
foo = foo + bar;

/*
     + : Addition             - : Subtraction
     * : Multiplication       / : Division
     % : Modulus Division

     ++ : Increase by 1       -- : Decrease by 1
*/

foo += 12;   // Addition assignment operator
foo -= 35;   // Subtraction assignment operator

int year = 2018;
char* message;

if (year > 2018) {
   message = "After 2018";
}
else if (year < 2018) {
   message = "Before 2018";
}
else {
   message = "The year is 2018!";
}

/*
   == : Equal to                   != : Not Equal to
   >  : Greater than               <  : Less than
   >= : Greater than or equal to   <= : Less than or equal to
*/

int foo = 0;

// While Loop
while (foo < 100) {
   foo++;
}

int sum = 0;
int i;

// For Loop
for (i = 0; i < 100; i++) {
   sum += i;   // adds all values from 0 to 99
}

// Declares the array "points" that can store 9 integers
int points[9];

points[0] = 716;
points[1] = 482;
printf("%d", points[1]);   // Prints 482

// Initialize at declaration
// Size of array automatically matches number of items
char grades[] = {'A', 'C', 'A', 'B'};

// Returns 1 (true) if negative, 0 (false) otherwise
int isNegative(int n) {
   return n < 0;
}

int answer = isNegative(-5);
if (answer) {
   printf("Number is negative!");
}

struct Person {
   char name[50];
   int age;
   int ssn;
};

// Initialize at declaration
struct Person man = {"Bob", 30, 123456789};

// Access members
printf("%s is %d years old", man.name, man.age);