Submission #57139

#	Time	Username	Problem	Language	Result	Execution time	Memory
57139		kriii	Tents (JOI18_tents)	C++17	100 / 100	142 ms	71716 KiB

tents

#include <stdio.h>

const long long mod = 1000000007;
long long d[3030][3030];

int main()
{
	int N,M; scanf ("%d %d",&N,&M);

	for (int i=0;i<=N;i++) for (int j=0;j<=M;j++){
		if (i == 0 || j == 0) d[i][j] = 1;
		else{
			d[i][j] = (d[i-1][j] + d[i-1][j-1] * j * 4) % mod;
			if (i >= 2) d[i][j] = (d[i][j] + d[i-2][j-1] * (i - 1) * j) % mod;
			if (j >= 2) d[i][j] = (d[i][j] + d[i-1][j-2] * j * (j - 1) / 2) % mod;
		}
	}

	printf ("%lld\n",(d[N][M]+mod-1)%mod);

	return 0;
}

Compilation message (stderr)

tents.cpp: In function 'int main()':
tents.cpp:8:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  int N,M; scanf ("%d %d",&N,&M);
           ~~~~~~^~~~~~~~~~~~~~~

• Subtask 1: 48 / 48
• Subtask 2: 52 / 52