I'm trying to solve the 1805 URI question:

  

A natural number is a non-negative integer (0, 1, 2, 3, 4, 5, ...). Your task in this problem is to calculate the sum of the natural numbers that are present in a given range [ A , B      For example, the sum of the natural numbers in the range [2, 5] is 14 = (2 + 3 + 4 + 5).

     

Input

     

Each test case contains two A and B integers (1 ≤ A ≤ B ≤ 10 < sup> 9 ), representing the lower and upper bound respectively.

     

Output

     

For each test case, the output consists of a line containing the sum of the natural numbers in the range.

But it is always giving error:

Idonotknowwhat'swrongwiththeresultsbeingthesameasthequestion.

Thecodeisthis:

#include<stdio.h>intmain(intargc,char**argv){longlongintn1,n2,i,j=0;scanf("%lld %lld",&n1,&n2);
    for(i=n1;i<=n2;i++)
    {
        j+=i;
    }
    printf("%lld\n",j);
    return 0;
}