Submission #401943

#	Time	Username	Problem	Language	Result	Execution time	Memory
401943		faresbasbs	Painting Walls (APIO20_paint)	C++14	63 / 100	1579 ms	14460 KiB

paint

#include <bits/stdc++.h>
#include "paint.h"
using namespace std;
int v1[100001],v2[100001];
vector<int> vals[100001];

int minimumInstructions(int n , int m , int K , vector<int> c , vector<int> A , vector<vector<int>> B){
	for(int i = 0 ; i < m ; i += 1){
		v1[i] = v2[i] = -1000000000;
		for(auto j : B[i]){
			vals[j].push_back(i);
		}
	}
	vector<int> q1,q2;
	for(int i : vals[c[n-1]]){
		q1.push_back(i);
		v1[i] = n-1;
	}
	vector<int> all;
	bool ok = 0;
	for(auto j : q1){
		if(v1[j]-(n-1) >= m-1){
			ok = 1;
		}
	}
	if(ok){
		all.push_back(n-1);
	}
	for(int i = n-2 ; i >= 0 ; i -= 1){
		for(auto j : vals[c[i]]){
			if(vals[c[i+1]].size() && vals[c[i+1]].back() >= (j+1)%m && 
				*lower_bound(vals[c[i+1]].begin(),vals[c[i+1]].end(),(j+1)%m) == (j+1)%m){
				q2.push_back(j);
				v2[j] = v1[(j+1)%m];
			}else{
				q2.push_back(j);
				v2[j] = i;
			}
		}
		for(auto j : q1){
			v1[j] = -1000000000;
		}
		for(auto j : q2){
			v1[j] = v2[j];
			v2[j] = -1000000000;
		}
		swap(q1,q2);
		bool ok = 0;
		for(auto j : q1){
			if(v1[j]-i >= m-1){
				ok = 1;
			}
		}
		if(ok){
			all.push_back(i);
		}
		q2.clear();
	}
	reverse(all.begin(),all.end());
	if(all.size() == 0 || all[0] != 0){
		return -1;
	}
	int pre = 0 , mx = 0 , cnt = 1;
	for(int i = 0 ; i < all.size() ; i += 1){
		if(pre+m >= all[i]){
			mx = all[i];
			continue;
		}
		if(mx == pre){
			return -1;
		}
		cnt += 1 , pre = mx;
		i -= 1;
	}
	if(pre+m == n){
		return cnt;
	}
	pre = mx , cnt += 1;
	if(pre+m == n){
		return cnt;
	}
	return -1;
}

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:64:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   64 |  for(int i = 0 ; i < all.size() ; i += 1){
      |                  ~~^~~~~~~~~~~~

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