字符串加解密(HJ29)

一：解题思路

二：完整代码示例 (C++版和Java版)

C++代码：

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>

using namespace std;

void encryString(string& s)
{
    for (int i = 0; i < s.size(); i++)
    {
        if (s[i] >= 'a' && s[i] < 'z')
        {
            s[i] = s[i] - 32 + 1;
        }
        else if(s[i] == 'z') 
            s[i] = 'A';
        else if (s[i] >= 'A' && s[i] < 'Z')
        {
            s[i] = s[i] + 32 + 1;
        }
        else if(s[i]=='Z') 
            s[i] = 'a';
        else if (s[i] >= '0' && s[i] < '9')
        {
            s[i] = s[i] + 1;
        }
        else if (s[i] == '9') 
            s[i] = '0';
    }
}

void decipString(string& s)
{
    for (int i = 0; i < s.size(); i++)
    {
        if (s[i] > 'a' && s[i] <= 'z')
        {
            s[i] = s[i] - 32 - 1;
        }
        else if (s[i] == 'a') 
            s[i] = 'Z';
        else if (s[i] > 'A' && s[i] <= 'Z')
        {
            s[i] = s[i] + 32 - 1;
        }
        else if (s[i] == 'A') 
            s[i] = 'z';
        else if (s[i] > '0' && s[i] <= '9')
        {
            s[i] = s[i] - 1;
        }
        else if (s[i] == '0') 
            s[i] = '9';
        
    }
}

int main()
{
    string s1 = "";
    string s2 = "";

    while (cin >> s1>>s2)
    {
        encryString(s1);
        cout << s1 << endl;
        decipString(s2);
        cout << s2 << endl;
    }

    return 0;
}