Submission #110131

#	Time	Username	Problem	Language	Result	Execution time	Memory
110131		popovicirobert	Snake Escaping (JOI18_snake_escaping)	C++14	100 / 100	1953 ms	36344 KiB

snake_escaping

#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
#define ll long long
#define ull unsigned long long
// 217
// 44

using namespace std;

int dp0[1 << 20], dp1[1 << 20];
char str[1 << 20];
int bit[20], sz;
int ans;

void bktQ(int p, int cnf) {
    if(p == sz) {
        ans += str[cnf] - '0';
    }
    else {
        bktQ(p + 1, cnf);
        bktQ(p + 1, cnf + (1 << bit[p]));
    }
}

void bkt0(int p, int cnf, int cnt) {
    if(p == sz) {
        if(cnt & 1) {
            ans -= dp0[cnf];
        }
        else {
            ans += dp0[cnf];
        }
    }
    else {
        bkt0(p + 1, cnf, cnt);
        bkt0(p + 1, cnf ^ (1 << bit[p]), cnt + 1);
    }
}

void bkt1(int p, int cnf, int cnt) {
    if(p == sz) {
        if(cnt & 1) {
            ans -= dp1[cnf];
        }
        else {
            ans += dp1[cnf];
        }
    }
    else {
        bkt1(p + 1, cnf, cnt);
        bkt1(p + 1, cnf ^ (1 << bit[p]), cnt + 1);
    }
}

int main() {
    //ifstream cin("A.in");
    //ofstream cout("A.out");
    int i, l, q;
    //ios::sync_with_stdio(false);
    //cin.tie(0), cout.tie(0);

    scanf("%d%d%s" ,&l,&q,str);

    for(int conf = 0; conf < (1 << l); conf++) {
        dp0[conf ^ ((1 << l) - 1)] = str[conf] - '0';
        dp1[conf] = str[conf] - '0';
    }

    for(int bit = 0; bit < l; bit++) {
        for(int conf = 0; conf < (1 << (l - 1)); conf++) {
            int cur = (conf & ((1 << bit) - 1)) + (1 << bit) + ((conf >> bit) << (bit + 1));
            dp0[cur] += dp0[cur ^ (1 << bit)];
            dp1[cur] += dp1[cur ^ (1 << bit)];
        }
    }

    while(q > 0) {
        q--;

        static char cur[20];
        scanf("%s" ,cur);
        reverse(cur, cur + l);

        int numq = 0, num0 = 0, num1 = 0;
        for(i = 0; i < l; i++) {
            if(cur[i] == '0') {
                num0++;
            }
            else if(cur[i] == '1') {
                num1++;
            }
            else {
                numq++;
            }
        }

        int mn = min(numq, min(num0, num1));
        int cnf = 0;
        ans = sz = 0;

        if(numq == mn) {

            for(i = 0; i < l; i++) {
                if(cur[i] == '?') {
                    bit[sz++] = i;
                }
                else {
                    cnf += (1 << i) * (cur[i] == '1');
                }
            }

            bktQ(0, cnf);
        }
        else if(num0 == mn) {

            for(i = 0; i < l; i++) {
                if(cur[i] == '0') {
                    bit[sz++] = i;
                }
                if(cur[i] != '1') {
                    cnf += (1 << i);
                }
            }

            bkt0(0, cnf, 0);
        }
        else if(num1 == mn) {

             for(i = 0; i < l; i++) {
                if(cur[i] == '1') {
                    bit[sz++] = i;
                }
                if(cur[i] != '0') {
                    cnf += (1 << i);
                }
            }

            bkt1(0, cnf, 0);
        }

        printf("%d\n" ,ans);

    }

    //cin.close();
    //cout.close();
    return 0;
}

Compilation message (stderr)

snake_escaping.cpp: In function 'int main()':
snake_escaping.cpp:62:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%s" ,&l,&q,str);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~
snake_escaping.cpp:81:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%s" ,cur);
         ~~~~~^~~~~~~~~~~

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