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Define a Macro to round a float value to nearest integer in C

C macro to round a float value to the integer: Here, we are implementing a program to convert a given float value to the nearest integer with the help of a Macro.
By IncludeHelp Last updated : March 10, 2024

Given a float value and we have to round the value to the nearest integer with the help of Macro in C language.

Macro Definition

    #define round(x) ((x)>=0?(long)((x)+0.5):(long)((x)-0.5))

Example

Input:
float val1=10.00f;
float val2=10.23f;
float val3=10.50f;
float val4=10.65f;

Output:
After round val1=10
After round val2=10
After round val3=11
After round val4=11

C program to define a Macro to round a float value to nearest integer

#include <stdio.h>

//Macro
#define round(x) ((x)>=0?(long)((x)+0.5):(long)((x)-0.5))

//Main code 
int main(void)
{
	float val1=10.00f;
	float val2=10.23f;
	float val3=10.50f;
	float val4=10.65f;

	printf("After round val1=%d\n",round(val1));
	printf("After round val2=%d\n",round(val2));
	printf("After round val3=%d\n",round(val3));
	printf("After round val4=%d\n",round(val4));

	return 0;
}

Output

After round val1=10
After round val2=10
After round val3=11
After round val4=11