Submission #1060623

#	Time	Username	Problem	Language	Result	Execution time	Memory
1060623		nvujica	Prisoner Challenge (IOI22_prison)	C++17	90 / 100	16 ms	1116 KiB

prison

#include <bits/stdc++.h>
#include "prison.h"

using namespace std;

const int x = 21;

vector<vector<int> > devise_strategy(int n) {
	vector <vector<int> > s(x + 1);
	for(int i = 0; i <= x; i++){
		s[i].resize(n + 1, 0);
	}
	
	for(int i = 0; i <= x; i++){
		int b, r;
		
		if(i <= 18){
			b = (i + 2) / 3;
			r = (i + 2) % 3;
		}
		else if(i <= 20){
			b = 7;
			r = (i + 1) % 2;
		}
		else {
			b = 8;
		}
		
		s[i][0] = b % 2;
		
		for(int val = 1; val <= n; val++){
			vector <int> mask;
			
			int val2 = val;
			
			mask.push_back(val2 % 4);
			val2 /= 4;
			
			mask.push_back(val2 % 2);
			val2 /= 2;
			
			for(int j = 0; j < 6; j++){
				mask.push_back(val2 % 3);
				val2 /= 3;
			}
			
			reverse(mask.begin(), mask.end());
			
			if(b == 8){
				if(mask[7] <= 1) s[i][val] = -1;
				else s[i][val] = -2;
				continue;
			}
			
			if(b == 0 || mask[b - 1] == r){
				if(b == 7){
					if(mask[b] == 0) s[i][val] = -2;
					else if(mask[b] == 3) s[i][val] = -1;
					else s[i][val] = 21;
				}
				else s[i][val] = b * 3 + 1 + mask[b];
			}
			else if(mask[b - 1] < r){
				s[i][val] = -1 - s[i][0];
			}
			else if(mask[b - 1] > r) s[i][val] = -2 + s[i][0];
		}
	}
	
//	for(int i = 0; i <= x; i++){
//		for(int j = 0; j <= n; j++){
//			cout << s[i][j] << ' ';
//		}
//		cout << endl;
//	}
	
	return s;
}

Compilation message (stderr)

prison.cpp: In function 'std::vector<std::vector<int> > devise_strategy(int)':
prison.cpp:66:9: warning: 'r' may be used uninitialized in this function [-Wmaybe-uninitialized]
   66 |    else if(mask[b - 1] > r) s[i][val] = -2 + s[i][0];
      |         ^~

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 80 / 90