Submission #21047

# Submission time Handle Problem Language Result Execution time Memory
21047 2017-04-04T05:06:57 Z sbansalcs Watching (JOI13_watching) C++14
50 / 100
113 ms 6540 KB
#include <iostream>
#include <algorithm>
using namespace std;
typedef long long ll;
const int N = 105;
ll arr[N];
int dp[N][N][N];
int n,p,q;

bool check(ll w)   {
    
    
    for (int i=n+1; i>=1; i--) {
        for (int j=0; j<=p; j++) {
            for (int k=0; k<=q; k++) {
                dp[i][j][k]=0;
                if(i==n+1)  {
                    dp[i][j][k]=1;
                }
                else    {
                    ll a;
                    if(j!=0)    {
                        a=arr[i]+w;
                        int lx=i+1,rx=n+1,mx;
                        while (lx<rx) {
                            mx= (lx+rx)/2;
                            if(arr[mx]>=a)  rx=mx;
                            else    lx=mx+1;
                        }
                        dp[i][j][k]|=dp[lx][j-1][k];
                    }
                    if(k!=0 && !dp[i][j][k])    {
                        a=arr[i]+2*w;
                        int lx=i+1,rx=n+1,mx;
                        while (lx<rx) {
                            mx= (lx+rx)/2;
                            if(arr[mx]>=a)  rx=mx;
                            else    lx=mx+1;
                        }
                        dp[i][j][k]|=dp[lx][j][k-1];
                    }
                }
                
            }
        }
    }
    
    
    
    return dp[1][p][q];
}

int main() {
    scanf("%d %d %d",&n,&p,&q);
    for (int i=1; i<=n; i++) {
        scanf("%lld",arr+i);
    }
    if(p+q>=n)  {
        cout<<1<<endl;return 0;
    }
    sort(arr+1,arr+1+n);
    arr[n+1]=2e9;
    int lx=1,rx=1e9,mx;
    while (lx<rx) {
        mx=(lx+rx)/2;
        if(check(mx))   rx=mx;
        else    lx=mx+1;
    }
    cout<<lx<<endl;
    return 0;
}

Compilation message

watching.cpp: In function 'int main()':
watching.cpp:54:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d %d",&n,&p,&q);
                               ^
watching.cpp:56:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%lld",arr+i);
                            ^

# Verdict Execution time Memory Grader output
1 Correct 0 ms 6540 KB Output is correct
2 Correct 0 ms 6540 KB Output is correct
3 Correct 0 ms 6540 KB Output is correct
4 Correct 0 ms 6540 KB Output is correct
5 Correct 0 ms 6540 KB Output is correct
6 Correct 0 ms 6540 KB Output is correct
7 Correct 0 ms 6540 KB Output is correct
8 Correct 3 ms 6540 KB Output is correct
9 Correct 3 ms 6540 KB Output is correct
10 Correct 43 ms 6540 KB Output is correct
11 Correct 49 ms 6540 KB Output is correct
12 Correct 113 ms 6540 KB Output is correct
13 Correct 0 ms 6540 KB Output is correct
14 Correct 0 ms 6540 KB Output is correct
15 Correct 3 ms 6540 KB Output is correct
# Verdict Execution time Memory Grader output
1 Runtime error 0 ms 6540 KB Execution killed because of forbidden syscall futex (202)
2 Halted 0 ms 0 KB -