oj.uz

Submission #225404

# Submission time Handle Problem Language Result Execution time Memory
225404 2020-04-20T13:50:05 Z brcode Skyscraper (JOI16_skyscraper) C++14
15 / 100
 6 ms 1792 KB 
#include <iostream>
#include <bits/stdc++.h>

using namespace std;
const int MAXN = 110;
const int MOD = 1e9+7;
int dp[MAXN][MAXN][1010][5];
int arr[MAXN];
int n,L;
int rec(int i,int j,int k,int l){
    //dp[i][j][k][l] = first i numbers, j connected components, k = total sum and l = number of endpoints on which numbers have been placed
    if(i>0 && (j<1||l>2||k>L)){
        return 0;
    }
    if(i==n){
        
        return (j==1 && l==2);
    }
    if(dp[i][j][k][l]!=-1){
        return dp[i][j][k][l];
    }
    int toadd = (arr[i+1]-arr[i])*(2*j-l) + k;//all positions adjacent to existing connected components must be incremented by the difference between adjacent elements in our array
    dp[i][j][k][l] = 0;
    dp[i][j][k][l] = (dp[i][j][k][l] + ((2*j-l)%MOD*rec(i+1,j,toadd,l)%MOD)%MOD)%MOD;//add on to an already existing connected component
    dp[i][j][k][l] = (dp[i][j][k][l] + ((j+1-l)%MOD*rec(i+1,j+1,toadd,l)%MOD)%MOD)%MOD;//add a new connected component
    dp[i][j][k][l] = (dp[i][j][k][l] + ((2-l)%MOD*rec(i+1,j+1,toadd,l+1)%MOD)%MOD)%MOD;//add a new connected component to an endpoint
    dp[i][j][k][l] = (dp[i][j][k][l] + ((2-l)%MOD*rec(i+1,j,toadd,l+1)%MOD)%MOD)%MOD;//extend an already existing connected component to an endpoint
    dp[i][j][k][l] = (dp[i][j][k][l] + ((j-1)%MOD*rec(i+1,j-1,toadd,l)%MOD)%MOD)%MOD;//merge 2 connected components
    return dp[i][j][k][l];
}
int main(){
    cin>>n>>L;
    for(int i=1;i<=n;i++){
        cin>>arr[i];
    }
    sort(arr+1,arr+n+1);
    for(int i=0;i<=n;i++){
        for(int j=0;j<=n;j++){
            for(int k=0;k<=L;k++){
                for(int l=0;l<=3;l++){
                    dp[i][j][k][l] = -1;
                }
            }
        }
    }
    
    cout<<rec(0,0,0,0)<<endl;
}

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 5 ms 384 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 1280 KB Output is correct
2 Correct 6 ms 1792 KB Output is correct
3 Correct 5 ms 1536 KB Output is correct
4 Correct 5 ms 1664 KB Output is correct
5 Correct 5 ms 1664 KB Output is correct
6 Correct 5 ms 1664 KB Output is correct
7 Correct 5 ms 1408 KB Output is correct
8 Correct 5 ms 1408 KB Output is correct
9 Correct 5 ms 1664 KB Output is correct
10 Correct 5 ms 1664 KB Output is correct

Subtask #3
0 / 80.0

# Verdict Execution time Memory Grader output
1 Incorrect 5 ms 384 KB Output isn't correct
2 Halted 0 ms 0 KB -