#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std;
using namespace atcoder;
#define rep(i,n)for (int i = 0; i < int(n); ++i)
#define rrep(i,n)for (int i = int(n)-1; i >= 0; --i)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
template<class T> void chmax(T& a, const T& b) {a = max(a, b);}
template<class T> void chmin(T& a, const T& b) {a = min(a, b);}
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<ll>;
using VVL = vector<VL>;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    string s;
    cin >> s;
    VI d;
    VVI idx(26);
    int n = s.size();
    rep(i, n) if (s[i] != '?') idx[s[i] - 'a'].push_back(i);
    while(true) {
        bool exist = false;
        rep(i, 26) if (!idx[i].empty()) exist = true;
        if (!exist) break;
        d.clear();
        int now = -1;
        rrep(i, 26) {
            int sj = lower_bound(all(idx[i]), now) - idx[i].begin();
            for(int j = sj; j < idx[i].size(); j++) d.push_back(idx[i][j]), now = idx[i][j];
            idx[i].resize(sj);
        }
    }
    int sz = d.size();
    if (d.empty()) {
        rep(i, n) s[i] = 'a';
    } else {
        int l = 0;
        rep(i, sz) {
            int r = d[i];
            for(int i = l; i < r; i++) if (s[i] == '?') s[i] = s[r];
            l = r;
        }
        for(int i = l; i < n; i++) if (s[i] == '?') s[i] = 'a';
    }
    cout << s << endl;
}