Sum
Time Limit: 2.0 second
Memory Limit: 1 000 K
Your task is to find the sum of all integer numbers lying between 1 and N inclusive.
1. Input
The input consists of a single integer N that is not greater than 10000 by it's absolute value.
2. Output
Write to the output file a single integer number that is the sum of all integer numbers lying between 1 and N inclusive.
3. Sample Input
{{{-3 }}}
4. Sample Output
{{{-5 }}}
http://acm.timus.ru/problem.aspx?space=1&num=1068