round() : Nearest integer value of a number

#include <stdio.h>
int main() {
printf("\nNumber = %.2f", round(12.38)); // Number = 12.00
printf("\nNumber = %.2f", round(12.89)); // Number = 13.00
printf("\nNumber = %.2f", round(-12.32)); // Number = -12.00
printf("\nNumber = %.2f", round(-12.95)); // Number = -13.00
return 0;
}

round(x) 

Example with integer variables

#include 
#include 
int main(void){
     int  x1,x2,x3,x4;
     x1=round(13.345);
     x2=round(12.656);
     x3=round(-13.21);
     x4=round(-14.67);
     printf("x1=%d , x2=%d,x3=%d,x4=%d", x1,x2,x3,x4);
     return 0;
}

x1=13, x2=13, x3=-13,x4=-15

Example with float variables

#include <stdio.h>
#include <math.h>
int main(void){
     float  x1,x2,x3,x4;
     x1=round(13.545);
     x2=round(12.656);
     x3=round(-13.51);
     x4=round(-14.67);
     printf("x1=%f , x2=%f,x3=%f,x4=%f", x1,x2,x3,x4);
     return 0;
}

x1=14.000000, x2=13.000000, x3=-14.000000,x4=-15.000000

Example 1: Rounding Positive and Negative Numbers

This example demonstrates how to use round() to round positive, negative, and zero values.

#include <stdio.h>
#include <math.h>

int main() {
    double num1 = 9.75, num2 = -9.25, num3 = 0.0;
    
    printf("round(%.2f) = %.2f\n", num1, round(num1));
    printf("round(%.2f) = %.2f\n", num2, round(num2));
    printf("round(%.2f) = %.2f\n", num3, round(num3));
    
    return 0;
}

round(9.75) = 10.00
round(-9.25) = -9.00
round(0.00) = 0.00

Example 2: Rounding Values with User Input

Allow users to input a number and see its rounded value using round().

#include <stdio.h>
#include <math.h>

int main() {
    double num;
    
    printf("Enter a number: ");
    scanf("%lf", &num);
    
    printf("The rounded value is: %.2f\n", round(num));
    
    return 0;
}

Enter a number: 5.67
The rounded value is: 6.00

Example 3: Rounding an Array of Numbers

This example rounds an array of floating-point numbers.

#include <stdio.h>
#include <math.h>

int main() {
    double nums[] = {3.14, -2.73, 5.99, -7.01};
    int n = sizeof(nums) / sizeof(nums[0]);
    
    for (int i = 0; i < n; i++) {
        printf("round(%.2f) = %.2f\n", nums[i], round(nums[i]));
    }
    
    return 0;
}

round(3.14) = 3.00
round(-2.73) = -3.00
round(5.99) = 6.00
round(-7.01) = -7.00