Submission #1695416


Source Code Expand

#include<cstdio>
#include<algorithm>
#include<cstring>
#include<cmath>
using namespace std;

const int maxn=3010;
int dp[maxn][maxn<<1][2];
int n,m,mod=1e9+7;

void add(int& x,int y){
	x+=y; if(x>=mod) x-=mod;
}

int main(){

	scanf("%d%d",&n,&m);
	for(int i=1;i<=n;i++) dp[0][i][0]=1;
	dp[0][0][1]=1;
	for(int i=0;i<m;i++){
		for(int j=0;j<=n;j++) for(int k=0;k<=1;k++){
			if(j){
				add(dp[i+1][j][k | (j==1)], dp[i][j][k]);
				add(dp[i+1][j-1][k | (j==1)], dp[i][j][k]);
			}
			if(n-j){
				add(dp[i+1][j+1][k], dp[i][j][k]);
				add(dp[i+1][j][k], dp[i][j][k]);
			}
		}
	}
	int ans=0;
	for(int i=0;i<=n;i++) add(ans, dp[m][i][1]);
	printf("%d",ans);
	return 0;
}

Submission Info

Submission Time
Task D - Piling Up
User ljs
Language C++14 (GCC 5.4.1)
Score 900
Code Size 705 Byte
Status AC
Exec Time 207 ms
Memory 140672 KB

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:17:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
                     ^

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 900 / 900
Status
AC × 3
AC × 33
Set Name Test Cases
Sample sample_01.txt, sample_02.txt, sample_03.txt
All sample_01.txt, sample_02.txt, sample_03.txt, sample_01.txt, sample_02.txt, sample_03.txt, subtask_1_01.txt, subtask_1_02.txt, subtask_1_03.txt, subtask_1_04.txt, subtask_1_05.txt, subtask_1_06.txt, subtask_1_07.txt, subtask_1_08.txt, subtask_1_09.txt, subtask_1_10.txt, subtask_1_11.txt, subtask_1_12.txt, subtask_1_13.txt, subtask_1_14.txt, subtask_1_15.txt, subtask_1_16.txt, subtask_1_17.txt, subtask_1_18.txt, subtask_1_19.txt, subtask_1_20.txt, subtask_1_21.txt, subtask_1_22.txt, subtask_1_23.txt, subtask_1_24.txt, subtask_1_25.txt, subtask_1_26.txt, subtask_1_27.txt
Case Name Status Exec Time Memory
sample_01.txt AC 1 ms 128 KB
sample_02.txt AC 1 ms 256 KB
sample_03.txt AC 104 ms 139904 KB
subtask_1_01.txt AC 24 ms 27776 KB
subtask_1_02.txt AC 25 ms 53760 KB
subtask_1_03.txt AC 89 ms 139904 KB
subtask_1_04.txt AC 66 ms 76544 KB
subtask_1_05.txt AC 153 ms 119936 KB
subtask_1_06.txt AC 89 ms 139904 KB
subtask_1_07.txt AC 95 ms 129664 KB
subtask_1_08.txt AC 41 ms 90624 KB
subtask_1_09.txt AC 159 ms 140288 KB
subtask_1_10.txt AC 207 ms 140672 KB
subtask_1_11.txt AC 85 ms 127616 KB
subtask_1_12.txt AC 54 ms 80640 KB
subtask_1_13.txt AC 82 ms 139776 KB
subtask_1_14.txt AC 49 ms 119296 KB
subtask_1_15.txt AC 25 ms 41600 KB
subtask_1_16.txt AC 100 ms 139904 KB
subtask_1_17.txt AC 36 ms 68096 KB
subtask_1_18.txt AC 39 ms 57984 KB
subtask_1_19.txt AC 59 ms 139776 KB
subtask_1_20.txt AC 104 ms 139904 KB
subtask_1_21.txt AC 13 ms 55680 KB
subtask_1_22.txt AC 32 ms 139648 KB
subtask_1_23.txt AC 16 ms 70016 KB
subtask_1_24.txt AC 33 ms 139648 KB
subtask_1_25.txt AC 1 ms 256 KB
subtask_1_26.txt AC 33 ms 139648 KB
subtask_1_27.txt AC 0 ms 128 KB