Submission #435160

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Source Code Expand

#include <iostream>
#include <cstdio>
#include <cassert>
#include <cstring>
#include <vector>
#include <valarray>
#include <array>
#include <queue>
#include <set>
#include <unordered_set>
#include <map>
#include <unordered_map>
#include <algorithm>
#include <cmath>
#include <complex>
#include <random>

using namespace std;
typedef long long ll;
typedef unsigned long long ull;

const int MN = 32;
const int MM = 200;
int n, m;
int x[MM], y[MM];

int z[MN][4];
int zc[MN];
int zcsm[MN], mc[MN];

int d[MN];

int p = 0;
int ma = -1;
int res = 0;

void dfs(int i) {
//    printf("dfs %d/%d %d %d\n", i, n, ma, res);
    if (i == n) {
        if (ma < p) {
            ma = p;
            res = 1;
        } else if (ma == p) {
            res++;
        }
        return;
    }
    if (p + zcsm[i] < ma) return;
    int co[2] = {};
    for (int j = 0; j < zc[i]; j++) {
        if (i < z[i][j]) continue;
        if (d[z[i][j]]) co[0]++;
        else co[1]++;
    }
    if (co[0] > co[1]) {
        d[i] = 0;
        p += co[0];
        dfs(i+1);
        p -= co[0];
        if (co[1]+mc[i] < co[0]) return;
        d[i] = 1;
        p += co[1];
        dfs(i+1);
        p -= co[1];
    } else {
        d[i] = 1;
        p += co[1];
        dfs(i+1);
        p -= co[1];
        if (co[0]+mc[i] < co[1]) return;
        d[i] = 0;
        p += co[0];
        dfs(i+1);
        p -= co[0];
    }
}

int solve() {
    for (int i = 0; i < m; i++) {
        int xx = x[i], yy = y[i];
        if (xx < yy) swap(xx, yy);
        z[xx][zc[xx]] = yy;
        zc[xx]++;
        mc[yy]++;
    }
    zcsm[n] = 0;
    for (int i = n-1; i >= 0; i--) {
        zcsm[i] = zcsm[i+1] + zc[i];
    }
    dfs(0);
    return res;
}



int main() {
    string s;
    cin >> s;
    int mc = (int)s.size()+1;
    mc /= 4;
    char in[MM][2];
    m = 0;
    set<char> allc;
    for (int i = 0; i < mc; i++) {
        in[m][0] = s[4*i];
        in[m][1] = s[4*i+2];
        allc.insert(in[m][0]);
        allc.insert(in[m][1]);
        if (in[m][0] == in[m][1]) continue;
        m++;
    }
    map<char, int> mp;
    n = 0;
    for (int i = 0; i < m; i++) {
        if (!mp.count(in[i][0])) {
            mp[in[i][0]] = n;
            n++;
        }
        if (!mp.count(in[i][1])) {
            mp[in[i][1]] = n;
            n++;
        }
    }

    int k = 1 << (allc.size()-n);
    for (int i = 0; i < m; i++) {
        x[i] = mp[in[i][0]];
        y[i] = mp[in[i][1]];
    }
    cout << k*solve() << endl;
    return 0;
}

Submission Info

Judge Result