Submission #1679735

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Source Code Expand

#include<bits/stdc++.h>
#define N 55
using namespace std;
const int mo=1e9+7;
int n,f[N][2*N][2*N],a[2*N],ans;
void inc(int &x,int y){ x=x+y>=mo ? x+y-mo : x+y;}
int main()
{
	int i,j,k,l,p,u,v;
	scanf("%d",&n);
	for(i=1;i<2*n;i++) scanf("%d",&a[i]);
	sort(a+1,a+2*n);
	f[n][1][1]=1,p=1;
	for(i=n;i>1;i--){
		u=(a[i]!=a[i-1]);
		v=(a[2*n-i]!=a[2*n-i+1]);
		for(j=1;j<=p;j++)
			for(k=1;k<=j;k++){
				if(!f[i][j][k]) continue;
				for(l=1;l<k+u;l++)
					inc(f[i-1][j+u+v-(k+u-l-1)][l],f[i][j][k]);
				for(l=j+u+v;l>k+u;l--)
					inc(f[i-1][j+u+v-(l-k-u-1)][k+u+1],f[i][j][k]);
				inc(f[i-1][j+u+v][k+u],f[i][j][k]);
			  }
		p+=u+v;
	  }
	for(i=1;i<=p;i++)
		for(j=1;j<=i;j++)
			inc(ans,f[1][i][j]);
	cout<<ans;
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:10:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
                ^
./Main.cpp:11:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  for(i=1;i<2*n;i++) scanf("%d",&a[i]);
                                      ^

Judge Result