Submission #738411

#	Time	Username	Problem	Language	Result	Execution time	Memory
738411		colossal_pepe	Painting Walls (APIO20_paint)	C++17	0 / 100	1 ms	300 KiB

paint

#include "paint.h"

#include <iostream>
#include <vector>
using namespace std;

int n, m, k;
vector<int> c, a;
vector<vector<int>> b;

vector<vector<int>> getLikedBy() {
    vector<vector<int>> ret(k);
    for (int i = 0; i < m; i++) {
        for (int j : b[i]) {
            ret[j].push_back(i);
        }
    }
    return ret;
}

int val(int i, int j, vector<vector<int>> &dp) {
    return (i < n ? dp[i][j] : 0);
}

int solve(vector<vector<int>> &liked_by) {
    // cout << "TF IS HAPPENING" << endl;
    if (n == 1) return (liked_by[c[0]].empty() ? -1 : 1);
    vector<vector<int>> dp(n);
    for (int i = 0; i < n; i++) {
        dp[i].resize(i ? liked_by[c[i - 1]].size() + 1 : 1, 0);
    }
    // cout << "EIKHANE ASCHE?" << endl;
    for (int i = n - 1; i >= 0; i--) {
        for (int j = 0; j < liked_by[c[i]].size(); j++) {
            dp[i].back() = max(dp[i].back(), 1 + val(i + 1, j, dp));
        }
        if (i == 0) continue;
        int j_cur = 0, j_prv;
        for (j_prv = 0; j_prv < liked_by[c[i - 1]].size(); j_prv++) {
            while (j_cur < liked_by[c[i]].size() and liked_by[c[i]][j_cur] <= liked_by[c[i - 1]][j_prv]) j_cur++;
            if (j_cur < liked_by[c[i]].size() and liked_by[c[i]][j_cur] == liked_by[c[i - 1]][j_prv] + 1) dp[i][j_prv] = 1 + val(i + 1, j_cur, dp);
        }
        if (liked_by[c[i]].front() == 0 and liked_by[c[i - 1]].back() == m - 1) dp[i][liked_by[c[i - 1]].size() - 1] = 1 + val(i + 1, 0, dp);
    }
    int ret = 0, start_at = (dp[0].back() >= m ? 0 : -1), needs_colour = 0;
    for (int i = 0; i < n; i++) {
        if (i == needs_colour) {
            if (start_at == -1) return -1;
            ret++;
            start_at = -1;
            needs_colour = i + m;
        }
        if (dp[i].back() >= m) start_at = i;
    }
    return ret;
}

int minimumInstructions(
    int N, int M, int K, vector<int> C,
    vector<int> A, vector<vector<int>> B) {
    n = N, m = M, k = K;
    c = C, a = A;
    b = B;
    vector<vector<int>> liked_by = getLikedBy();
    return solve(liked_by);
}

Compilation message (stderr)

paint.cpp: In function 'int solve(std::vector<std::vector<int> >&)':
paint.cpp:34:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |         for (int j = 0; j < liked_by[c[i]].size(); j++) {
      |                         ~~^~~~~~~~~~~~~~~~~~~~~~~
paint.cpp:39:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |         for (j_prv = 0; j_prv < liked_by[c[i - 1]].size(); j_prv++) {
      |                         ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
paint.cpp:40:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   40 |             while (j_cur < liked_by[c[i]].size() and liked_by[c[i]][j_cur] <= liked_by[c[i - 1]][j_prv]) j_cur++;
      |                    ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
paint.cpp:41:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |             if (j_cur < liked_by[c[i]].size() and liked_by[c[i]][j_cur] == liked_by[c[i - 1]][j_prv] + 1) dp[i][j_prv] = 1 + val(i + 1, j_cur, dp);
      |                 ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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