https://codefights.com/challenge/jzs6k2FedHaDfCWtv

reverseChallenge.cpp

#include <bits/stdc++.h>
using namespace std;

string reverseChallenge(string s) {
    string t, ans;
    vector<int> len;
    int l = 0;
    s += ' ';
    for(size_t i = 0; i < s.size(); i++) {
        if(s[i]==' ') {
            len.push_back(l);
            l=0;
        }
        else {
            l++;
            t += s[i];
        }
    }
    reverse(t.begin(), t.end());
    for(size_t i = 0; i < t.size(); i++) {
        if('a' <= t[i] && t[i] <= 'z')
            t[i]='z'-(t[i]-'a');
    }

    int idx = 0;
    for(size_t i = 0; i < len.size(); i++) {
        ans += t.substr(idx, len[i]);
        idx += len[i];
        if(i != len.size()-1) ans += ' ';
    }
    return ans;
}

int main() {
    string s;
    getline(cin, s);
    cout<<reverseChallenge(s)<<endl;
    return 0;
}