Submission #1792486

---

Source Code Expand

# include <bits/stdc++.h>

using namespace std;

# define REP(i, a, b) for(int i = a; i <= b; ++ i)
# define REPG(i, h, x) for(int i = h[x]; ~i; i = edge[i].next)
# define CLR(i, a) memset(i, a, sizeof(i))
# define REPD(i, a, b) for(int i = a; i >= b; -- i)

const int N = 15 + 5, N_ = 15, M = 15 * 14 / 2 + 5, MOD = 1e9 + 7;
typedef long long ll;
//f[i][S] 
// g[i][S]

bool e[N][N];
int n, m, S;
int g[N][(1 << 17)], f[N][(1 << 17)];
int dp[(1 << 17)], id[N], pw[300];

inline void inc(int &a, int b) { a = (a + b) % MOD; }

void pre() {
	REP(i, 1, n) {
		REP(j, 0, S) {
			f[i][j] = f[i][j - (j&-j)] + e[i][id[j&-j]];
		}
	}
	REP(i, 1, n) {
		REP(j, 0, S) {
			int p = j & -j;
			if(e[i][id[p]]) inc(g[i][j], (g[i][j - p] * 2 + 1) % MOD);
			else g[i][j] = g[i][j - p] % MOD;
		}
	}
}
int main() {
	scanf("%d%d", &n, &m);
	S = (1 << n) - 1;
	pw[0] = 1;
	REP(i, 1, n) id[(1 << i - 1)] = i;
	REP(i, 1, m) pw[i] = 1ll * pw[i - 1] * 2 % MOD; //1ll
	REP(i, 1, m) {
		int x, y; scanf("%d%d", &x, &y);
		e[x][y] = 1;
	}
    pre();
    dp[0] = 1;
	REP(s, 1, S) {
		for(int t = (s - 1) & s; ; -- t, t &= s) { // origin
//			if(((t & 1) ^ (t & 2)) == 0) {
			 if (((((s^t)&1)&&(t&2)) == 0) && ((((s^t)&2)&&(t&1)) == 0)) {
				int tmp = 1, tmp2 = 0;
				for(int j = t; j; j -= j & -j) tmp = 1ll * tmp * g[id[j & -j]][t ^ s] % MOD;
				for(int j = t ^ s; j; j -= j & -j) inc(tmp2, f[id[j & -j]][t]);
				inc(dp[s], 1ll * (1ll * (1ll * pw[tmp2] % MOD) * tmp % MOD) * dp[t] % MOD);
			}
			if(!t) break;
		}
	}
    printf("%d\n", (((pw[m] - dp[S]) % MOD) + MOD) % MOD);
	return 0;
}
/*5 10
2 4
3 4
2 5
2 3
1 2
3 5
1 3
1 5
4 5
1 4

*/

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:37:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &n, &m);
                       ^
./Main.cpp:43:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   int x, y; scanf("%d%d", &x, &y);
                                  ^

Judge Result