Problem E: Character - Toggling Cases

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Time Limit $1$ 秒/Second(s) Memory Limit $512$ 兆字节/Megabyte(s)
提交总数 $216$ 正确数量 $117$
裁判形式 标准裁判/Standard Judge 我的状态 尚未尝试
难度 分类标签 STL 字符串 模拟

Toggling Cases 

Write a program which converts uppercase/lowercase letters to lowercase/uppercase for a given string.

A string is given in a line.
Print the converted string in a line. Note that you do not need to convert any characters other than alphabetical letters.
fAIR, LATER, OCCASIONALLY CLOUDY.
Fair, later, occasionally cloudy.
The length of the input string < 1200