답안 #227662

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
227662 2020-04-28T10:34:17 Z imsifile 유적 3 (JOI20_ruins3) C++
100 / 100
913 ms 3768 KB
#include<stdio.h>

typedef long long lld;
const lld mod=1000000007;

int N, chk[1212], pos[666], neg[666], xs[666];
lld dy[666][666], pw[1212], fac[1212], rfac[1212], rgop[1212], all[666], sums[666];

int cc[666], ba[666], tmp[666], rcn[666];

lld rev(lld a){
	lld g=1;
	for(int r=mod-2; r; r>>=1){
		if(r&1) g=g*a%mod;
		a=a*a%mod;
	}
	return g;
}

lld perm(lld a, lld b){
	if(a<b) return 0;
	return fac[a]*rfac[a-b]%mod;
}

int main(){
	scanf("%d", &N);
	for(int i=1; i<=2*N; i++) chk[i]=1;
	pw[0]=fac[0]=rfac[0]=1;
	for(int i=1; i<=2*N; i++){
		pw[i]=pw[i-1]*((mod+1)/2)%mod;
		fac[i]=fac[i-1]*i%mod;
		rfac[i]=rev(fac[i]);
		rgop[i]=rev(4*i-2);
	}
	for(int i=1; i<=N; i++){
		if(i==1) all[i]=1;
		else all[i]=fac[2*i]*pw[i]%mod*rgop[i]%mod*rfac[i]%mod*rfac[i]%mod;
	}

	for(int i=0; i<N; i++){
		scanf("%d", &neg[i]);
		chk[neg[i]]=-1;
	}
	for(int i=1, pcn=0; i<=2*N; i++){
		if(chk[i]>0) pos[pcn++]=i;
		chk[i]+=chk[i-1];
		if(chk[i]<0){ puts("0"); return 0; }
	}
	xs[N]=N;
	for(int i=0; i<N; i++) xs[i]=(neg[i]-1+chk[neg[i]-1])/2;

	for(int i=N; i>=0; i--){
		for(int k=i+1; k<=N; k++) sums[k]=0;
		for(int j=i; j>=0; j--){
			for(int k=i+1; k<=N; k++){
				sums[k]+=dy[k][j]*all[k-i]%mod*perm(xs[j]-i,k-i)%mod*rfac[i-j]%mod;
				sums[k]%=mod;
			}
			if(i==N && j==N) dy[i][j]=1;
			else if(i==xs[j]) dy[i][j]=dy[i][j+1]*chk[neg[j]-1]%mod;
			else if(i>xs[j]) dy[i][j]=0;
			else {
				for(int k=i+1; k<=N; k++) dy[i][j]+=sums[k]*fac[i-j]%mod;
				dy[i][j]%=mod;
			}
			for(int k=i+1; k<=N; k++){
				sums[k]+=dy[k][j]*all[k-i]%mod*(mod-perm(xs[j-1]-i,k-i))%mod*rfac[i-j]%mod;
				sums[k]%=mod;
			}
		}
	}
	printf("%lld\n", dy[0][0]);
	return 0;
}

Compilation message

ruins3.cpp: In function 'int main()':
ruins3.cpp:26:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &N);
  ~~~~~^~~~~~~~~~
ruins3.cpp:41:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &neg[i]);
   ~~~~~^~~~~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 384 KB Output is correct
2 Correct 4 ms 384 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 4 ms 384 KB Output is correct
5 Correct 4 ms 384 KB Output is correct
6 Correct 4 ms 384 KB Output is correct
7 Correct 4 ms 384 KB Output is correct
8 Correct 4 ms 384 KB Output is correct
9 Correct 5 ms 384 KB Output is correct
10 Correct 4 ms 384 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 384 KB Output is correct
2 Correct 4 ms 384 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 4 ms 384 KB Output is correct
5 Correct 4 ms 384 KB Output is correct
6 Correct 4 ms 384 KB Output is correct
7 Correct 4 ms 384 KB Output is correct
8 Correct 4 ms 384 KB Output is correct
9 Correct 5 ms 384 KB Output is correct
10 Correct 4 ms 384 KB Output is correct
11 Correct 5 ms 640 KB Output is correct
12 Correct 5 ms 640 KB Output is correct
13 Correct 5 ms 640 KB Output is correct
14 Correct 4 ms 384 KB Output is correct
15 Correct 5 ms 384 KB Output is correct
16 Correct 5 ms 640 KB Output is correct
17 Correct 5 ms 384 KB Output is correct
18 Correct 6 ms 640 KB Output is correct
19 Correct 5 ms 640 KB Output is correct
20 Correct 5 ms 640 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 384 KB Output is correct
2 Correct 4 ms 384 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 4 ms 384 KB Output is correct
5 Correct 4 ms 384 KB Output is correct
6 Correct 4 ms 384 KB Output is correct
7 Correct 4 ms 384 KB Output is correct
8 Correct 4 ms 384 KB Output is correct
9 Correct 5 ms 384 KB Output is correct
10 Correct 4 ms 384 KB Output is correct
11 Correct 5 ms 640 KB Output is correct
12 Correct 5 ms 640 KB Output is correct
13 Correct 5 ms 640 KB Output is correct
14 Correct 4 ms 384 KB Output is correct
15 Correct 5 ms 384 KB Output is correct
16 Correct 5 ms 640 KB Output is correct
17 Correct 5 ms 384 KB Output is correct
18 Correct 6 ms 640 KB Output is correct
19 Correct 5 ms 640 KB Output is correct
20 Correct 5 ms 640 KB Output is correct
21 Correct 441 ms 3428 KB Output is correct
22 Correct 451 ms 3456 KB Output is correct
23 Correct 421 ms 3452 KB Output is correct
24 Correct 448 ms 3448 KB Output is correct
25 Correct 5 ms 384 KB Output is correct
26 Correct 5 ms 384 KB Output is correct
27 Correct 5 ms 384 KB Output is correct
28 Correct 417 ms 3448 KB Output is correct
29 Correct 5 ms 384 KB Output is correct
30 Correct 913 ms 3448 KB Output is correct
31 Correct 674 ms 3448 KB Output is correct
32 Correct 813 ms 3584 KB Output is correct
33 Correct 862 ms 3428 KB Output is correct
34 Correct 684 ms 3768 KB Output is correct
35 Correct 787 ms 3576 KB Output is correct
36 Correct 889 ms 3704 KB Output is correct