C program to find the sum of odd and even numbers from 1 to N.

#include <stdio.h>
void main()
{
int i, num, sum_of_odd = 0, sum_of_even = 0;
printf("Enter the value of num\n");
scanf("%d", &num);
for (i = 1; i <= num; i++)
{
if (i % 2 == 0)
sum_of_even = sum_of_even + i;
else
sum_of_odd = sum_of_odd + i;
}
printf("Sum of all odd numbers = %d\n", sum_of_odd);
printf("Sum of all even numbers = %d\n", sum_of_even);
}

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C, C Program to Calculate the Sum of Odd & Even Numbers, C Programs