1159 - Sum of Consecutive Even Numbers

#include<stdio.h>
int main()
{
    int a=1,b,i,sum=0;
    while(1)
    {
        scanf("%d",&a);
        if(a==0){
            break;
        }
        if(a%2!=0){
            a=a+1;
        }
        for(i=1; i<=5; i++)
        {
            sum=sum+a;
            a=a+2;
        }
        printf("%d\n",sum);
        sum=0;
    }
    return 0;
}