//sum of all numbers from 1 to n using while loop
#include<stdio.h>
int main()
{
int n,i=1,sum=0;
printf("Enter n= \n");
scanf("%d",&n);
printf("Number is : %d\n",n);
while(i<=n)
{
sum=sum+i;
i++;
}
printf("Sum of 1 to %d = %d",n,sum);
return 0;
}