题解 | #字符串排序#

#include <iostream>
#include <string>
#include<vector>
using namespace std;

int main() {
    vector<string> map (27, "");
    string str, res = "";
    getline(cin, str);              // 01注意cin的局限性
    int len = str.size();
    char chars[1001] = {'\0'};
    for(int i = 0; i < len; ++i)
    {
        if(str[i] >= 'a' && str[i] <= 'z') map[str[i]-96] += str[i];
        else if(str[i] >= 'A' && str[i] <= 'Z') map[str[i]-64] += str[i];
        else chars[i] = str[i];
    }
    // for(int i = 1; i <= 26; ++i) cout << map[i] << endl;
    int idx = 0;
    for(int i = 1; i <= 26; ++i)
    {
        int sublen = map[i].size();
        for(int j = 0; j < sublen;)
        {
            if(chars[idx] != '\0') idx++;
            else chars[idx++] = map[i][j++];  // 02 同步递增
        }
    }
    for(int i = 0; i <= 1000; ++i) if(chars[i] != '\0') res += chars[i];  // 03
    cout << res;
}
// 64 位输出请用 printf("%lld")