Submission #1204564

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Source Code Expand

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

int dp[50][100][100];
bool Lflag[50], Rflag[50];
int arr[100];

const int MOD = 1e9+7;
void add(int& target, int delta){
    target = (target + delta)%MOD;
}

int main(){
    int N; scanf("%d",&N);
    for(int i=0;i<2*N-1;i++) scanf("%d",arr+i);
    sort(arr,arr+2*N-1);

    for(int i=1;i<N;i++) if(arr[N-1-(i-1)] != arr[N-1-i])
        Lflag[i] = true;
    for(int i=1;i<N;i++) if(arr[N-1+(i-1)] != arr[N-1+i])
        Rflag[i] = true;

    dp[0][0][0] = 1;
    for(int i=0;i<N-1;i++) for(int L=0;L<=2*i+1;L++) for(int R=0;R<=2*i+1;R++){
        int nL = L + (Lflag[i+1]?1:0), nR = R + (Rflag[i+1]?1:0);
        int cur = dp[i][L][R];
        add(dp[i+1][nL][nR], cur);
        for(int j=1;j<=nL;j++)
            add(dp[i+1][nL-j][nR+1], cur);
        for(int j=1;j<=nR;j++)
            add(dp[i+1][nL+1][nR-j], cur);
    }

    int ans = 0;
    for(int i=0;i<2*N-1;i++)for(int j=0;j<2*N-1;j++)
        add(ans, dp[N-1][i][j]);
    printf("%d\n", ans);
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:15:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     int N; scanf("%d",&N);
                          ^
./Main.cpp:16:47: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     for(int i=0;i<2*N-1;i++) scanf("%d",arr+i);
                                               ^

Judge Result