Operators and examples

1. Addition (+): 7 + 2 gives 9.
2. Subtraction (-): 7 - 2 gives 5.
3. Multiplication (*): 7 * 2 gives 14.
4. Division (/): 7 / 2 gives 3 when both operands are integers. 7.0 / 2 gives 3.5.
5. Remainder (%): 7 % 2 gives 1, the remainder after integer division. Both operands must have integer type.

Integer and floating-point division

Integer division discards the fractional part towards zero. Thus -7 / 2 gives -3. If a floating-point operand is present, floating-point division is used after the required conversions. To calculate a fractional average from integers, write (double)total / count with a non-zero count.

Example

For a = 17 and b = 5, a / b is 3 and a % b is 2. The relationship is 17 = 3 * 5 + 2. This explains the difference between quotient and remainder.

Important points

Never divide by zero or use zero as the divisor of %. Keep results within the allowed type range: signed integer overflow has no defined result in C. Integer division must also have a representable result. Floating-point calculations may contain small rounding errors.

C program and output

/* CodeBhavya | PPS AR25 | Learning example */
#include <stdio.h>
int main(void)
{
    int a = 7, b = 2;
    printf("sum = %d\n", a + b);
    printf("difference = %d\n", a - b);
    printf("product = %d\n", a * b);
    printf("integer division = %d\n", a / b);
    printf("remainder = %d\n", a % b);
    printf("real division = %.1f\n", (double)a / b);
    return 0;
}

sum = 9
difference = 5
product = 14
integer division = 3
remainder = 1
real division = 3.5

Key points

• 7 / 2 and 7.0 / 2 have different results.
• % is an integer operator.