Submission #697501

#	Time	Username	Problem	Language	Result	Execution time	Memory
697501		sharaelong	Painting Walls (APIO20_paint)	C++17	63 / 100	1600 ms	266796 KiB

paint

#include "paint.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

const int MAX_N = 1e5 + 1;

int minimumInstructions(int n, int m, int k, vector<int> C, vector<int> A, vector<vector<int>> B) {
    vector<vector<int>> likes(k);
    for (int i=0; i<m; ++i) {
        for (int j=0; j<A[i]; ++j) {
            likes[B[i][j]].push_back(i);
        }
    }
    // for (int i=0; i<k; ++i) {
    //     for (int x: likes[i]) cout << x << ' ';
    //     cout << endl;
    // }
    
    vector<vector<int>> nxt(n);
    vector<vector<bool>> processed(n);
    for (int i=0; i<n; ++i) {
        nxt[i].resize(likes[C[i]].size(), -1);
        processed[i].resize(likes[C[i]].size(), false);
    }

    vector<int> pnt(n, 0);
    for (int i=0; i+1<n; ++i) {
        const vector<int>& cands = likes[C[i+1]];
        for (int j=0; j<likes[C[i]].size(); ++j) {
            int x = likes[C[i]][j];
            if (x+1 < m) {
                while (pnt[i+1] < cands.size() && cands[pnt[i+1]] <= x) pnt[i+1]++;
                if (pnt[i+1] < cands.size() && cands[pnt[i+1]] == x+1) nxt[i][j] = pnt[i+1];
            } else {
                if (!cands.empty() && cands[0] == 0) nxt[i][j] = 0;
            }
        }
    }
    // for (int i=0; i<n; ++i) {
    //     for (int x: nxt[i]) cout << x << ' ';
    //     cout << endl;
    // }

    vector<int> okay(n+1, 0);
    for (int i=0; i<n; ++i) {
        for (int j=0; j<likes[C[i]].size(); ++j) {
            if (!processed[i][j]) {
                processed[i][j] = true;
                int ii = i, jj = j;
                while (ii < n && nxt[ii][jj] != -1) {
                    jj = nxt[ii][jj];
                    ii++;
                    processed[ii][jj] = true;
                }

                if (ii == n) ii--;
                if (ii-i+1 >= m) {
                    okay[i]++;
                    okay[ii-m+2]--;
                }
            }
        }
    }
    for (int i=1; i<okay.size(); ++i) okay[i] += okay[i-1];
    // for (int i=0; i<n; ++i) cout << okay[i] << ' ';
    // cout << endl;

    vector<int> valid_pos;
    for (int i=0; i<n; ++i) {
        if (okay[i] > 0) valid_pos.push_back(i);
    }
    if (valid_pos.empty() || valid_pos[0] > 0) return -1;

    int ans = 1;
    int curr = 0;
    while (curr + m < n) {
        auto it = upper_bound(valid_pos.begin(), valid_pos.end(), curr+m);
        if (*prev(it) == curr) return -1;
        curr = *prev(it);
        ans++;
    }
    return ans;
}

Compilation message (stderr)

paint.cpp: In function 'int minimumInstructions(int, int, int, std::vector<int>, std::vector<int>, std::vector<std::vector<int> >)':
paint.cpp:30:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |         for (int j=0; j<likes[C[i]].size(); ++j) {
      |                       ~^~~~~~~~~~~~~~~~~~~
paint.cpp:33:33: warning: comparison of integer expressions of different signedness: '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'} and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |                 while (pnt[i+1] < cands.size() && cands[pnt[i+1]] <= x) pnt[i+1]++;
paint.cpp:34:30: warning: comparison of integer expressions of different signedness: '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'} and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |                 if (pnt[i+1] < cands.size() && cands[pnt[i+1]] == x+1) nxt[i][j] = pnt[i+1];
paint.cpp:47:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |         for (int j=0; j<likes[C[i]].size(); ++j) {
      |                       ~^~~~~~~~~~~~~~~~~~~
paint.cpp:65:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |     for (int i=1; i<okay.size(); ++i) okay[i] += okay[i-1];
      |                   ~^~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 15 / 15
• Subtask 3: 13 / 13
• Subtask 4: 23 / 23
• Subtask 5: 0 / 37