Submission #1077679

#	Time	Username	Problem	Language	Result	Execution time	Memory
1077679		coolboy19521	Beautiful row (IZhO12_beauty)	C++17	Compilation error	0 ms	0 KiB

beauty

#include "bits/stdc++.h"
#define ll long long

using namespace std;

const int sz = 22;

bool vi[1ll << sz][sz];
ll dp[1ll << sz][sz];
int tw[sz], tr[sz];
int a[sz], n;

bool matc(int i, int j) {
    if (tw[i] == tw[j] || tr[i] == tr[j])
        return true;
    return false;
}

ll go(int i, ll bt) {
    if (bt == (1ll << n) - 1) return 1ll;
    int& v = vi[bt][i];
    ll& r = dp[bt][i];
    if (v) return r;
    v = true;
    for (int j = 0; j < n; j ++) {
        int f = bt & (1ll << j);
        if (!f && matc(i, j))
            r += go(j, bt | (1 << j));
    }
    return r;
}

void zero() {
    for (int i = 0; i < (1ll << n); i ++)
        for (int j = 0; j < n; j ++)
            dp[i][j] = vi[i][j] = 0;
}

signed main() {
    cin >> n;

    for (int i = 0; i < n; i ++)
        cin >> a[i];

    for (int i = 0; i < n; i ++) {
        for (int cn = a[i]; 0 < cn; cn /= 2)
            tw[i] += cn % 2;
        for (int cn = a[i]; 0 < cn; cn /= 3)
            tr[i] += 1 == cn % 3;
    }

    ll cn = 0;

    for (int i = 0; i < n; i ++) {
        zero();
        cn += go(i, 1ll << i);
    }

    cout << cn << '\n';
}

Compilation message (stderr)

beauty.cpp: In function 'long long int go(int, long long int)':
beauty.cpp:21:22: error: cannot bind non-const lvalue reference of type 'int&' to an rvalue of type 'int'
   21 |     int& v = vi[bt][i];
      |              ~~~~~~~~^