[1331] La La La - Sum
- 时间限制: 1000 ms 内存限制: 65535 K
- 问题描述
-
I have a integer m, and the other n numbers, can you find how many pairs of two integers in these n numbers that the sum of these two integers is equal to m?
- 输入
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Input until EOF.
First line will contain two integers m (0<m<10000) and n (0<n<10000), and then n integers follow in next line. Each integer is x (0<x<10000).
- 输出
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Print the number of these pair of integers.
- 样例输入
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100 5 1 2 50 98 99
- 样例输出
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2
- 提示
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无
- 来源
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Hungar
- 操作
-
