Submission #995904

#	Time	Username	Problem	Language	Result	Execution time	Memory
995904		Neco_arc	Snake Escaping (JOI18_snake_escaping)	C++17	100 / 100	593 ms	46564 KiB

snake_escaping

#include <bits/stdc++.h>
//#include <bits/debug.hpp>

#define ll long long
#define all(x) x.begin(), x.end()
#define Neco "Snake Escaping"
#define resp(x) sort(all(x)), x.resize(unique(all(x)) - x.begin())
#define getbit(x,i) ((x >> i)&1)
#define _left id * 2, l, mid
#define _right id * 2 + 1, mid + 1, r
#define cntbit(x) __builtin_popcountll(x)
#define fi(i, a, b) for(int i = a; i <= b; i++)
#define fid(i, a, b) for(int i = a; i >= b; i--)
#define maxn (int) 2e6 + 7

using namespace std;

const ll mod = 1e9 + 7; //972663749
const ll base = 911382323;

int N, q;
int a[maxn], f[2][maxn];

int CASE(int type, int P, int L) {
    int ans = 0;
    for(int x = P; ; x = (x - 1) & P)
    {
        int w = (cntbit(P) - cntbit(x)) & 1 ? -1 : 1;
        ans += w * f[type][x | L];
        if(x == 0) break;
    }
    return ans;
}

void solve()
{

    cin >> N >> q;
    fi(i, 0, (1 << N) - 1) {
        char x; cin >> x;
        a[i] = x - '0';
    }

    fi(i, 0, (1 << N) - 1) {
        f[0][(1 << N) - 1 - i] = a[i];
        f[1][i] = a[i];
    }

    fi(j, 0, N - 1) fi(x, 0, (1 << N) - 1) {
        if(getbit(x, j))
        {
            f[0][x] += f[0][x ^ (1 << j)];
            f[1][x] += f[1][x ^ (1 << j)];
        }
    }


    fi(_, 1, q)
    {
        string s; cin >> s;
        int A = 0, B = 0, C = 0;
        int ans = 0;

        fi(i, 0, N - 1) {
            if(s[N - 1 - i] == '0') A += (1 << i);
            else if(s[N - 1 - i] == '1') B += (1 << i);
            else C += (1 << i);
        }

        int cA = cntbit(A), cB = cntbit(B), cC = cntbit(C);

        if(cA <= min(cB, cC)) ans = CASE(0, A, C);
        else if(cB <= min(cA, cC)) ans = CASE(1, B, C);
        else
        {
            for(int x = C; ; x = (x - 1) & C) {
                ans += a[x | B];
                if(x == 0) break;
            }
        }

        cout << ans << '\n';
    }



}


int main()
{

    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    if(fopen(Neco".inp", "r")) {
        freopen(Neco".inp", "r", stdin);
        freopen(Neco".out", "w", stdout);
    }


    int nTest = 1;
//    cin >> nTest;


    while(nTest--)
    {
        solve();
    }


    return 0;
}

Compilation message (stderr)

snake_escaping.cpp: In function 'int main()':
snake_escaping.cpp:98:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   98 |         freopen(Neco".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
snake_escaping.cpp:99:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   99 |         freopen(Neco".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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