题解 | 排序危机

#include <bits/stdc++.h>
using namespace std;
const int N = 100086;
char arr[N];
char str1[N];
char str2[N];
//分别将数字，小写字母，大写字母分开输入，归类进对应的数组，再按顺序输出即可
int main()
{
    int n;
    cin >> n;
    int p = 0, q = 0, w = 0;
    for (int i = 0; i < n; i++)
    {
        char c;
        cin >> c;
        if (c <= '9' && c >= '0')
            arr[p++] = c;
        else if (c <= 'z' && c >= 'a')
            str1[q++] = c;
        else if (c <= 'Z' && c >= 'A')
            str2[w++] = c;
    }
    for (int i = 0; i < q; i++)
    {
        cout << str1[i];
    }
    for (int i = 0; i < p; i++)
    {
        cout << arr[i];
    }
    for (int i = 0; i < w; i++)
    {
        cout << str2[i];
    }
    return 0;
}