Submission #838560

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Source Code Expand

#include<bits/stdc++.h>
using namespace std;


const int maxn = 5000+100;
typedef long long LL;
const LL mod = 1e9+7;
LL dp[2][maxn][maxn];

char s[maxn];
int n;

int main()
{
    //freopen("./test.txt","r",stdin);
    scanf("%d",&n);
    scanf("%s",s+1);
    int m = strlen(s+1);
    memset(dp,0,sizeof(dp));
    int p = 0;
    dp[0][0][0] = 1;
    for(int i = 0;i < n;++i)
    {
        memset(dp[p^1],0,sizeof(dp[p^1]));
        for(int j = 0;j <= m;++j)
            for(int nl = j;nl <= i;++nl)
            {
                if(dp[p][j][nl] == 0) continue;

//                if(i == 1)
//                printf("**** %d  %d   %d\n",j,nl,dp[p][j][nl]);
                if(j == m)
                {
                    dp[p^1][j][nl+1] = (dp[p^1][j][nl+1] + 2*dp[p][j][nl])%mod;
                    if(nl > j)
                        dp[p^1][j][nl-1] = (dp[p^1][j][nl-1] + dp[p][j][nl])%mod;
                    else
                        dp[p^1][j-1][nl-1] = (dp[p^1][j-1][nl-1] + dp[p][j][nl])%mod;
                }
                else
                {
                    if(j == nl)
                    {
                        dp[p^1][j+1][nl+1] = (dp[p^1][j+1][nl+1] + dp[p][j][nl])%mod;
                        dp[p^1][j][nl+1] = (dp[p^1][j][nl+1] + dp[p][j][nl])%mod;

//                        if(i == 0 && j == 0 && nl == 0)
//                            printf("*** %d\n",dp[p^1][nxtj][nxtl]);
                        int nxtl = max(nl-1,0);
                        int nxtj = nxtl;
                        dp[p^1][nxtj][nxtl] = (dp[p^1][nxtj][nxtl] + dp[p][j][nl])%mod;
                    }
                    else
                    {
                        dp[p^1][j][nl+1] = (dp[p^1][j][nl+1] + 2*dp[p][j][nl])%mod;
                        dp[p^1][j][nl-1] = (dp[p^1][j][nl-1] + dp[p][j][nl])%mod;

                    }

                }


            }
        p ^= 1;
//        if(i == 1)
//            printf("*** %d\n",dp[p][0][0]);
    }

    LL res = dp[p][m][m];
    printf("%lld\n",res);

    return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:16:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
                   ^
./Main.cpp:17:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%s",s+1);
                    ^

Judge Result