Calculate the sum of all numbers between two given numbers.
  #include <stdio.h>

int main(void)
{
int num1, num2, tmp, sum = 0;

printf("\nEnter two numbers :");
scanf("%d%d",&num1, &num2);

if(num1 > num2)
{
tmp = num1;
num1 = num2;
num2 = tmp;
}

do
{
sum += num1;
num1++;
}while(num1 <= num2);

printf("\nSum = %d", sum);


return 0;
}