Submission #920240

#	Time	Username	Problem	Language	Result	Execution time	Memory
920240		Unforgettablepl	Snake Escaping (JOI18_snake_escaping)	C++17	100 / 100	1369 ms	33012 KiB

snake_escaping

#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#include <bits/stdc++.h>
using namespace std;

#define int long long

int DP1[1048576];
int DP2[1048576];
int arr[1048576];
int idx[6];

inline int preprocess(const string &s,char c){
    int ans = 0;
    int cnt = 0;
    #pragma GCC unroll 20
    #pragma GCC ivdep
    for(int bit=0;bit<s.size();bit++){
        if(s[bit]==c){
            idx[cnt++]=bit;
        } else if(s[bit]=='?'){
            if(c=='1')ans|=(1<<bit);
        } else {
            if(s[bit]=='1')ans|=(1<<bit);
        }
    }
    return ans;
}

inline int applymask(int qu,int mask,int cnt){
    #pragma GCC unroll 20
    #pragma GCC ivdep
    for(int bit=0;bit<cnt;bit++){
        if(mask&(1<<bit))qu|=(1<<idx[bit]);
    }
    return qu;
}

int32_t main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int l,q;
    cin >> l >> q;
    for(int mask=0;mask<(1<<l);mask++){
        char a;cin>>a;a-='0';
        DP1[mask]=DP2[mask]=arr[mask]=a;
    }
    for(int bit=0;bit<20;bit++){
        for(int mask=0;mask<(1<<20);mask++){
            if(mask&(1<<bit)){
                DP2[mask^(1<<bit)]+=DP2[mask];
            } else {
                DP1[mask|(1<<bit)]+=DP1[mask];
            }
        }
    }
    for(int i=1;i<=q;i++){
        string s;cin>>s;
        reverse(s.begin(),s.end());
        int c1=0,c0=0,cq=0;
        for(char&j:s) {
            if(j=='1')c1++;
            else if(j=='0')c0++;
            else if(j=='?')cq++;
        }
        if(cq<=6){
            int qu = preprocess(s,'?');
            int ans = 0;
            for(int mask=0;mask<(1<<cq);mask++){
                ans+=arr[applymask(qu,mask,cq)];
            }
            cout<<ans<<'\n';
            continue;
        }
        if(c1<=6){
            int qu = preprocess(s,'1');
            int ans = 0;
            for(int mask=0;mask<(1<<c1);mask++){
                if(__builtin_parity(mask)==(c1&1)){
                    ans+=DP1[applymask(qu,mask,c1)];
                } else {
                    ans-=DP1[applymask(qu,mask,c1)];
                }
            }
            cout<<ans<<'\n';
            continue;
        }
        if(c0<=6){
            int qu = preprocess(s,'0');
            int ans = 0;
            for(int mask=0;mask<(1<<c0);mask++){
                if(__builtin_parity(mask)){
                    ans-=DP2[applymask(qu,mask,c0)];
                } else {
                    ans+=DP2[applymask(qu,mask,c0)];
                }
            }
            cout<<ans<<'\n';
            continue;
        }
    }
}

Compilation message (stderr)

snake_escaping.cpp: In function 'long long int preprocess(const string&, char)':
snake_escaping.cpp:18:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   18 |     for(int bit=0;bit<s.size();bit++){
      |                   ~~~^~~~~~~~~

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