描述

把一个字符串中所有出现的大写字母都替换成小写字母，同时把小写字母替换成大写字母。

输入

输入一行：待互换的字符串。

输出

输出一行：完成互换的字符串（字符串长度小于80）。

样例输入

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样例输出

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题解

#include <iostream>
using namespace std;
int main()
{
    char a[9999];
    int i = 0;
    cin.getline(a,80);
    for(int i = 0;a[i];i++)
    {
        if(a[i] >= 'a' && a[i] <= 'z') 
            a[i] -= 32; 
        else if(a[i] >= 'A' && a[i] <= 'Z')
            a[i] += 32;
    }
    for(int i = 0;a[i];i++)
        cout<<a[i];
    cout<<endl;
    return 0;
}