Submission #964774

#	Time	Username	Problem	Language	Result	Execution time	Memory
964774		12345678	Snake Escaping (JOI18_snake_escaping)	C++17	100 / 100	1530 ms	42320 KiB

snake_escaping

#include <bits/stdc++.h>

using namespace std;

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")

const int nx=(1<<20)+5;

int l, q, a[nx], sub[nx], super[nx];
char c;
string s;

int main()
{
    cin.tie(NULL)->sync_with_stdio(false);
    cin>>l>>q;
    for (int i=0; i<(1<<l); i++) cin>>c, a[i]=sub[i]=super[i]=c-'0';
    for (int i=0; i<l; i++) for (int j=0; j<(1<<l); j++) if (j&(1<<i)) sub[j]+=sub[j^(1<<i)];
    for (int i=0; i<l; i++) for (int j=(1<<l)-1; j>=0; j--) if (!(j&(1<<i))) super[j]+=super[j^(1<<i)];
    while (q--)
    {
        cin>>s;
        reverse(s.begin(), s.end());
        int tmp=0;
        vector<int> zero, one, qrs;
        for (int i=0; i<l; i++)
        {
            if (s[i]=='0') zero.push_back(i);
            if (s[i]=='1') one.push_back(i);
            if (s[i]=='?') qrs.push_back(i);
        }
        if (zero.size()<=(l/3))
        {
            for (int i=0; i<l; i++) if (s[i]=='1') tmp+=(1<<i);
            if (zero.empty()) cout<<super[tmp]<<'\n';
            else
            {
                int sz=zero.size(), res=0;
                for (int i=0; i<(1<<sz); i++)
                {
                    int vl=tmp;
                    for (int j=0; j<sz; j++) if ((i&(1<<j))) vl+=(1<<zero[j]);
                    //cout<<"debug "<<i<<' '<<vl<<'\n';
                    if ((__builtin_popcount(i)%2)==0) res+=super[vl];
                    else res-=super[vl];
                }
                cout<<res<<'\n';
            }
        }
        else if (one.size()<=(l/3))
        {
            for (int i=0; i<l; i++) if (s[i]=='?') tmp+=(1<<i);
            if (one.empty()) cout<<sub[tmp]<<'\n';
            else
            {
                int sz=one.size(), res=0;
                for (int i=0; i<(1<<sz); i++)
                {
                    int vl=tmp;
                    for (int j=0; j<sz; j++) if (i&(1<<j)) vl+=(1<<one[j]);
                    if ((sz-__builtin_popcount(i))%2==0) res+=sub[vl];
                    else res-=sub[vl];
                }
                cout<<res<<'\n';
            }     
        }
        else
        {
            for (int i=0; i<l; i++) if (s[i]=='1') tmp+=(1<<i);
            if (qrs.empty()) cout<<a[tmp]<<'\n';
            else
            {
                int sz=qrs.size(), res=0;
                for (int i=0; i<(1<<sz); i++)
                {
                    int vl=tmp;
                    for (int j=0; j<sz; j++) if (i&(1<<j)) vl+=(1<<qrs[j]);
                    res+=a[vl];
                }
                cout<<res<<'\n';
            }
        }
    }
}

// 00011???

Compilation message (stderr)

snake_escaping.cpp: In function 'int main()':
snake_escaping.cpp:33:24: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   33 |         if (zero.size()<=(l/3))
      |             ~~~~~~~~~~~^~~~~~~
snake_escaping.cpp:51:28: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   51 |         else if (one.size()<=(l/3))
      |                  ~~~~~~~~~~^~~~~~~

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