https://hack.codingblocks.com/contests/c/916/107
#include<bits/stdc++.h>
using namespace std;
int main() {
string s;
cin>>s;
sort(s.begin(),s.end());
map<char,int> map;
int n=s.length();
if(n==0){
return 0;
}
for(int i=0;i<n;i++){
if(map.find(s[i])!=map.end()){
map[s[i]]++;
}
else
map[s[i]]=1;
}
if(n>0){
for(auto i:map){
cout<<i.first<<i.second;
}
}
return 0;
}