Submission #659928

#	Time	Username	Problem	Language	Result	Execution time	Memory
659928		a_aguilo	Bank (IZhO14_bank)	C++14	100 / 100	572 ms	123484 KiB

bank

#include<bits/stdc++.h>

using namespace std;

int n, m;

int getSum(int mask, int banknotes[]){
    int ans = 0;
    for(int i = 0; i < m; ++i){
        if(mask & (1 << i) ) ans+= banknotes[i];
    }
    return ans;
}

int CanWePay(int person, int mask, vector<vector<int>>& DP, unordered_map<int, vector<int>>& WaysToPay, int salaries[]){
    if(person == n) return true;
    if(mask == ((1<<n)-1)) return false;
    if(DP[mask][person] != -1) return DP[mask][person];
    DP[mask][person] = 0;
    for(int payMask: WaysToPay[salaries[person]]){
        if(!(mask & payMask)){
            if(CanWePay(person+1, mask|payMask, DP, WaysToPay, salaries)){
                DP[mask][person] = 1;
                break;
            }
        }
    }
    return DP[mask][person];
}
int main(){
    cin.tie(NULL);
    ios::sync_with_stdio(false);
    int MaxSal;
    cin >> n >> m;
    int salaries[n];
    int banknotes[m];
    cin >> salaries[0];
    MaxSal = salaries[0];
    for(int i = 1; i < n; ++i) {
        cin >> salaries[i];
        MaxSal = max(MaxSal, salaries[i]);
    }
    for(int i = 0; i < m; ++i) cin >> banknotes[i];
    unordered_map <int, vector<int>> WaysToArrive;
    WaysToArrive.reserve(MaxSal);
    for(int mask = 1; mask < (1<<m); ++mask){
        int SumOfNotes = getSum(mask,banknotes);
        if(SumOfNotes > MaxSal) continue;
        if(WaysToArrive.find(SumOfNotes)== WaysToArrive.end()) WaysToArrive[SumOfNotes] = {mask};
        else WaysToArrive[SumOfNotes].push_back(mask);
    }
    vector<vector<int>> DP(1<<m, vector<int>(n, -1));
    if(CanWePay(0, 0, DP, WaysToArrive, salaries)) cout << "YES" << endl;
    else cout << "NO" << endl;
    return 0;
}

• Subtask 1: 19 / 19
• Subtask 2: 25 / 25
• Subtask 3: 27 / 27
• Subtask 4: 29 / 29