Submission #367234

#	Time	Username	Problem	Language	Result	Execution time	Memory
367234		piddddgy	Collecting Stamps 3 (JOI20_ho_t3)	C++11	0 / 100	2079 ms	424 KiB

ho_t3

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#define cerr if(false) cerr
#define watch(x) cerr << (#x) << " is " << (x) << endl;
#define endl '\n'
#define ld long double
#define int long long
#define pii pair<int, int>
#define fi first
#define se second
#define sz(a) (int)(a).size()
#define all(x) (x).begin(), (x).end()

const int maxn = 15;

bool vis[5000][maxn][300];

int n, l;
int x[maxn], t[maxn];

int bits(int num) {
    int res = 0;
    for(int i = 0; i < 30; i++) {
        if(num & (1LL << i)) res++;
    }

    return res;
}
int ans = 0;
void dfs(int mask, int cur, int time) {
    ans = max(ans, bits(mask));
    cerr << "on " << cur << " with " << time << endl;
    for(int i = 0; i < n; i++) {
        if((1 << i) & mask) continue;

        int dis = abs(x[cur]- x[i]);
        dis = min(dis, l-dis);

        if(time+dis <= t[i]) {
            dfs(mask | (1 << i), i, time+dis);
        }
    }
}

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

    cin >> n >> l;
    for(int i = 0; i < n; i++) {
        cin >> x[i];
    }

    for(int i = 0; i < n; i++) {
        cin >> t[i];
    }

    for(int i = 0; i < n; i++) {
        int dis = min(x[i], l-x[i]);

        if(dis <= t[i]) {
            dfs(1 << i, i, dis);
        } else {
            dfs(0, i, dis);
        }
    }

    cout << ans << endl;
}

/*

[bitmask][current][time] 

9 600 000

6 25
3 4 7 17 21 23
11 7 17 10 8 10
-> 4


Did you read the bounds?
Did you make typos?
Are there edge cases (N=1?)
Are array sizes proper?
Integer overflow?
DS reset properly between test cases?
Is using long longs causing TLE?
Are you using floating points?
*/

• Subtask 1: 0 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 75