Submission #780037

# Submission time Handle Problem Language Result Execution time Memory
780037 2023-07-12T05:55:15 Z 이동현(#10007) Sparklers (JOI17_sparklers) C++17
0 / 100
0 ms 340 KB
#include <bits/stdc++.h>
#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#define int long long
using namespace std;

const int NS = (int)1e5 + 4;
int n, k, t;
int a[NS];
int mn[1004][1004], mx[1004][1004];

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    cin >> n >> k >> t;
    --k;
    for(int i = 0; i < n; ++i){
        cin >> a[i];
    }
    int low = 0, high = (int)1e9, mid;
    while(low < high){
        mid = low + high >> 1;
        mn[k][k] = a[k] - t * mid;
        mx[k][k] = a[k] + t * mid;

        for(int i = n - 1; i >= 0; --i){
            for(int j = i + 1; j < n; ++j){
                mn[i][j] = (int)1e18;
                mx[i][j] = -(int)1e18;

                int l = mn[i + 1][j], r = mx[i + 1][j];
                r = min(r, a[i] + (j - i) * t * mid);
                l = max(l, a[i] - (j - i) * t * mid);
                if(l <= r){
                    mx[i][j] = max(mx[i][j], r + t * mid);
                    mn[i][j] = min(mn[i][j], l - t * mid);
                }

                l = mn[i][j - 1], r = mx[i][j - 1];
                r = min(r, a[j] + (j - i) * t * mid);
                l = max(l, a[j] - (j - i) * t * mid);
                if(l <= r){
                    mx[i][j] = max(mx[i][j], r + t * mid);
                    mn[i][j] = min(mn[i][j], l - t * mid);
                }
            }
        }

        if(mn[0][n - 1] != (int)1e18){
            high = mid;
        }
        else{
            low = mid + 1;
        }
    }

    cout << low << '\n';

    return 0;
}

Compilation message

sparklers.cpp: In function 'int main()':
sparklers.cpp:24:19: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   24 |         mid = low + high >> 1;
      |               ~~~~^~~~~~
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Incorrect 0 ms 340 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Incorrect 0 ms 340 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Incorrect 0 ms 340 KB Output isn't correct
3 Halted 0 ms 0 KB -