Submission #1039301

#	Time	Username	Problem	Language	Result	Execution time	Memory
1039301		phong	Snake Escaping (JOI18_snake_escaping)	C++17	100 / 100	923 ms	43332 KiB

snake_escaping

//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma")
//#pragma GCC optimize("unroll-loops")
#include<bits/stdc++.h>

#define ll long long
const int nmax = 4e5 + 5, N = 1e5;
const ll oo = 1e9;
const int lg = 31, M = 2, mod = 1e6;
#define pii pair<ll, ll>
#define fi first
#define se second
#define debug(a, n) for(int i = 1; i <= n; ++i) cout << a[i] << ' '; cout << "\n";
#define endl "\n"
#define task "code"
using namespace std;

int L, q;
string s;
int F[1 << 20], G[1 << 20], cnt[1 << 20];
int bit(int msk, int x){
    return msk>> x & 1;
}
main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
//    freopen(task".inp", "r", stdin);
//    freopen(task".out", "w", stdout);
    cin >> L >> q;
    cin >> s;

    for(int i = 0; i < (1 << L) ; ++i){
        int c1 = 0, c2 = 0;
        for(int k = 1; k <= L; ++k){
            if(bit(i, L - k)){
                c1 += (1 << (k - 1));
            }
            else c2 += (1 << (k - 1));
        }
        cnt[c1] += s[i] - '0';
        F[c1] += s[i] - '0';
        G[c2] += s[i] - '0';
    }
    for(int i = 0; i < L; ++i){
        for(int msk = 0; msk < (1 << L); ++msk){
            if(!bit(msk, i)){
                F[msk ^ (1 << i)] += F[msk];
                G[msk ^ (1 << i)] += G[msk];
            }
        }
    }
    string tmp;
    vector<int> c0, c1, c2;
    while(q--){
        cin >> tmp;
        c0.clear(); c1.clear();c2.clear();
        for(int i = 0; i < L; ++i){
            char x = tmp[i];
            if(x == '0'){
                c0.push_back(i);
            }
            else if(x == '1'){
                c1.push_back(i);
            }
            else c2.push_back(i);
        }
        if((int)c1.size() <= 6){
//                cout << "%";
            int res = 0;
            for(auto p : c1) res += (1 << p);
            for(auto p : c2) res += (1 << p);
            ll ans = 0;
            for(int msk = 0; msk < (1 << c1.size()); ++msk){
                int cur = res;
                for(int i = 0; i < c1.size(); ++i){
                    if(bit(msk, i)){
                        cur ^= (1 << c1[i]);
                    }
                }
                int s = __builtin_popcount(msk);
                if(s & 1) ans -= F[cur];
                else ans += F[cur];
            }
            cout << ans << endl;
        }
        else if((int)c0.size() <= 6){
//                cout << "?";
            int res = 0;
            for(auto p : c0) res += (1 << p);
            for(auto p : c2) res += (1 << p);
            ll ans = 0;
            for(int msk = 0; msk < (1 << c0.size()); ++msk){
                int cur = res;
                for(int i = 0; i < c0.size(); ++i){
                    if(bit(msk, i)){
                        cur ^= (1 << c0[i]);
                    }
                }
                int s = __builtin_popcount(msk);
                if(s & 1) ans -= G[cur];
                else ans += G[cur];
            }
            cout << ans << endl;
        }
        else{
//            cout << "#";
            int res = 0;
            for(auto p : c1) res += (1 << p);
            int ans = 0;
            for(int msk = 0; msk < (1 << c2.size()); ++msk){
                int cur = res;
                for(int i = 0; i < c2.size(); ++i){
                    if(bit(msk, i)){
                        cur ^= (1 << c2[i]);
                    }
                }
                ans += cnt[cur];
            }
            cout << ans << endl;
        }
    }
}
/*
3 5
12345678
000
0??
1?0
?11
???

3 1
12345678
???
*/

Compilation message (stderr)

snake_escaping.cpp:24:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   24 | main(){
      | ^~~~
snake_escaping.cpp: In function 'int main()':
snake_escaping.cpp:75:34: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   75 |                 for(int i = 0; i < c1.size(); ++i){
      |                                ~~^~~~~~~~~~~
snake_escaping.cpp:94:34: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   94 |                 for(int i = 0; i < c0.size(); ++i){
      |                                ~~^~~~~~~~~~~
snake_escaping.cpp:112:34: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  112 |                 for(int i = 0; i < c2.size(); ++i){
      |                                ~~^~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 10 / 10
• Subtask 4: 53 / 53
• Subtask 5: 25 / 25