Submission #1773070

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Source Code Expand

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

typedef long long int LLI;
const LLI MOD = 1e9+7;

int N;
int M;
int C[258];
LLI dp[258][258][258];
LLI conv[258][258][258];

int main() {
  scanf("%d", &N);
  
  for (int i=0; i<N; i++) {
    scanf("%d", &C[i]);
  }

  if (C[0] != 1) {
    puts("0");
    return 0;
  }

  for (int i=0; i<N; i++) {
    dp[i][i+1][0] = 1;
    conv[i][i+1][0] = dp[i][i+1][0];
    for (int j=1; j<=N; j++) {
      conv[i][i+1][j] = (conv[i][i+1][j-1]+dp[i][i+1][j])%MOD;
    }
  }

  for (int w=2; w<=N; w++) {
    for (int l=0; l<N; l++) {
      int r = l+w;
      if (r > N) continue;
      for (int k=l+1; k<r; k++) {
        dp[l][r][C[k]] = (conv[l][k][C[k]-1]*conv[k][r][N])%MOD;
      }

      conv[l][r][0] = dp[l][r][0];
      for (int k=1; k<=N; k++) {
        conv[l][r][k] = (conv[l][r][k-1]+dp[l][r][k])%MOD;
      }
    }
  }
  printf("%lld\n", conv[0][N][N]);
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:14:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &N);
                  ^
./Main.cpp:17:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &C[i]);
                       ^

Judge Result