题解

#include<bits/stdc++.h>
using namespace std;
struct node{
    char s;
    int sum;
}a[10010];
bool cmp(node x,node y){
    return x.s < y.s;
}
int main() {
    string s;
    cin >> s;
    vector<char> ve;
    map<char, int> lp;
    for(int i = 0;i < s.size();i++){
        if (lp.find(s[i]) == lp.end()) {
            ve.push_back(s[i]);
            lp[s[i]] = 1;
        } else {
            lp[s[i]]++;
        }
    }
    for (int i = 0;i < ve.size();i++) {
        a[i].s = ve[i];
        a[i].sum = lp[ve[i]];
    }
    sort(a,a + ve.size(),cmp);
    for (int i = 0;i < ve.size();i++) {
        cout << a[i].s << ":" << a[i].sum << endl;
    }
    return 0;
}