题解 | #找位置#

简答的哈希

#include <iostream>
#include <map>
#include <vector>
#include <set>
using namespace std;

int main() {
    string s;
    while (cin >> s) {
        map<char, vector<int>> m;
        set<char> st;
        for (int i = 0; i < s.length(); i++) {
            m[s[i]].push_back(i);
        }
        for (auto c: s) {
            if (st.find(c) == st.end()) {
                vector<int> t = m[c];
                if (t.size() <= 1) continue;
                for (int i = 0; i < t.size(); i++) {
                    if (i == 0) {
                        cout << c << ":" << t[i];
                    } else {
                        cout << "," << c << ":" << t[i];
                    }
                }
                cout << endl;
                st.insert(c);
            }
        }   
    }
}