1244: 用while循环求1+2+3+...+n的和(07级)wk

Memory Limit:128 MB Time Limit:1.000 S
Judge Style:Text Compare Creator:
Submit:36 Solved:21

Description

输入一个数字n。运用while语句  求1+2+3+.....+n=?

Input

一个数字n

Output

输出1+2+3+.....+n的结果

Sample Input Copy

100

Sample Output Copy

5050