Submission #322409

#	Time	Username	Problem	Language	Result	Execution time	Memory
322409		Karen124	Global Warming (CEOI18_glo)	C++14	38 / 100	108 ms	2028 KiB

glo

#include <bits/stdc++.h>
     
using namespace std;
     
#define ll long long int 
#define F first
#define S second
#define pb push_back
 
const ll N = 2e5 + 10;
const ll LOG = 50;
const ll MOD = 1e9 + 7;
const ll INF = 1e9 + 10;
int n, X, a[N], b[N], dp[2][N], ans, pd[2][N];
int LIS(int l, int r, int add){
    int len = 0, p = 0, cn = 0;
    for (int i = 0; i <= n + 5; i++){
        b[i] = 0;
    }
    for (int i = 1; i <= n; i++){
        p = lower_bound(b, b + len, a[i] + (l <= i && i <= r) * add) - b;
        b[p] = a[i] + (l <= i && i <= r) * add;
        len = max(len, p + 1);
    }
    if (l == 0 && r == 0){
        cout << len << '\n';
        exit(0);
    }
    return len;
}
int main() {
    cin >> n >> X;
    for (int i = 1; i <= n; i++){
        cin >> a[i];
    }
    if (X == 0) {LIS(0, 0, 0);}
    else if (n <= 50 && X <= 50){
        for (int l = 1; l <= n; l++){
            for (int r = l; r <= n; r ++){
                for (int i = -X; i <= X; i++){
                    ans = max(ans, LIS(l, r, i));
                }
            }
        }
        cout << ans << '\n';
    }
    else if (n <= 1000){
        for (int i = 1; i <= n; i++){
            dp[0][i] = dp[1][i] = 1;
            dp[0][i] = max(dp[0][i], pd[0][i] + 1);
            
            for (int j = 0; j <= n + 5; j++) b[j] = 0;
            int len = 0, p = 0;
            for (int j = i; j >= 1; j--){
                p = lower_bound(b, b + len, -(a[j] + X)) - b;
                b[p] = -(a[j] + X);
                len = max(len, p + 1);
                if (j) dp[1][i] = max(dp[1][i], pd[1][j] + p + 1);
                else   dp[1][i] = max(dp[1][i], len);
            }
            
            for (int j = i + 1; j <= n; j++){
                if (a[i] < a[j])     pd[0][j] = max(dp[0][i], pd[0][j]);
                if (a[i] < a[j] + X) pd[1][j] = max(dp[0][i], pd[1][j]);
            }

            ans = max({ans, dp[0][i], dp[1][i]});
        }
        cout << ans << '\n';
    }
    else { // penis
        return 0;
    }
    return 0;
}

Compilation message (stderr)

glo.cpp: In function 'int LIS(int, int, int)':
glo.cpp:16:25: warning: unused variable 'cn' [-Wunused-variable]
   16 |     int len = 0, p = 0, cn = 0;
      |                         ^~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 13 / 13
• Subtask 4: 10 / 10
• Subtask 5: 0 / 20
• Subtask 6: 0 / 17
• Subtask 7: 0 / 25