Submission #688279

#	Time	Username	Problem	Language	Result	Execution time	Memory
688279		Matteo_Verz	Bigger segments (IZhO19_segments)	C++17	13 / 100	1 ms	1236 KiB

segments

#include <bits/stdc++.h>
#ifdef BLAT
    #include "debug/debug.hpp"
#else
    #define debug(x...)
#endif

using namespace std;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int n;
    cin >> n;

    vector <int> v(1 + n);
    vector <long long> sp(1 + n);
    vector <vector <int>> dp(1 + n, vector <int>(1 + n, -1));

    int lastjump = 1;
    for (int i = 1; i <= n; i++) {
        cin >> v[i];
        sp[i] = sp[i - 1] + v[i];

        dp[i][1] = 0;
        int cp = lastjump;
        for (int jumps = max(1, lastjump - 1); jumps <= min(n, lastjump + 1); jumps++) {
            int st, dr, mid;
            st = 1; dr = i - 1;
            while (st <= dr) {
                mid = (st + dr) >> 1;
                if (dp[mid][jumps - 1] == -1)
                    st = mid + 1;
                else if (sp[i] - sp[mid] >= sp[mid] - sp[dp[mid][jumps - 1]]) {
                    st = mid + 1;
                    dp[i][jumps] = mid;
                    cp = max(cp, jumps);
                } else 
                    dr = mid - 1;
            }

            /*for (int j = 1; j < i; j++) {
                if (dp[j][jumps - 1] != -1 && sp[i] - sp[j] >= sp[j] - sp[dp[j][jumps - 1]]) {
                    dp[i][jumps] = j;
                    cp = max(cp, jumps);
                }
            }*/
        }

        lastjump = cp;
    }

    /*for (int i = 1; i <= n; i++, cerr << '\n')
        for (int j = 1; j <= n; j++)
            cerr << dp[i][j] << '\t';*/
    int maxjumps = 1;
    for (int i = 1; i <= n; i++)
        if (dp[n][i] != -1)
            maxjumps = max(maxjumps, i);
    
    cout << maxjumps << '\n';
    
    return 0;
}

• Subtask 1: 13 / 13
• Subtask 2: 0 / 14
• Subtask 3: 0 / 10
• Subtask 4: 0 / 36
• Subtask 5: 0 / 27