Submission #333362

#	Time	Username	Problem	Language	Result	Execution time	Memory
333362		limabeans	Plus Minus (BOI17_plusminus)	C++17	12 / 100	1 ms	492 KiB

plusminus

#include <bits/stdc++.h>
using namespace std;

template<typename T>
void out(T x) { cout << x << endl; exit(0); }
#define watch(x) cout << (#x) << " is " << (x) << endl





using ll = long long;
const ll mod = 1e9 + 7;

const int maxn = 6;


int n,m,k;
ll dp[maxn][1<<maxn];
int g[maxn][maxn];





bool compat(int mask1, int mask2) {
    for (int j=1; j<m; j++) {
	vector<int> w(2,0);
	for (int k=j-1; k<=j; k++) {
	    w[mask1>>k&1]++;
	    w[mask2>>k&1]++;
	}
	if (!(w[0]==2 && w[1]==2)) return false;
    }
    return true;
}

int main() {
    ios_base::sync_with_stdio(false); cin.tie(0);  cout.tie(0);

    memset(g,-1,sizeof(g));

    cin>>n>>m>>k;
    while (k--) {
	char op;
	int r,c;
	cin>>op>>r>>c;
	--r; --c;
	g[r][c]=(op=='+'?1:0);
    }


    for (int i=0; i<n; i++) {
	for (int mask=0; mask<(1<<m); mask++) {

	    bool ok = true;

	    for (int j=0; j<m; j++) {
		if (g[i][j]!=-1) {
		    if ((mask>>j&1)!=g[i][j]) {
			ok = false;
		    }
		}
	    }


	    if (!ok) continue;

	    if (i==0) {
		dp[i][mask] = 1;
	    } else {
		for (int pmask=0; pmask<(1<<m); pmask++) {
		    if (compat(pmask, mask)) {
			dp[i][mask] += dp[i-1][pmask];
			dp[i][mask] %= mod;
		    }
		}
	    }
	}
    }



    ll res = 0;
    for (int mask=0; mask<(1<<m); mask++) {
	res += dp[n-1][mask];
	res %= mod;
    }

    cout<<res<<endl;    
    
    return 0;
}

• Subtask 1: 12 / 12
• Subtask 2: 0 / 42
• Subtask 3: 0 / 46