oj.uz

Submission #263165

# Submission time Handle Problem Language Result Execution time Memory
263165 2020-08-13T13:46:33 Z user202729 Robots (APIO13_robots) C++17
60 / 100
 833 ms 163844 KB 
// 2
#ifndef LOCAL
#define NDEBUG 1
#endif
#include<bits/stdc++.h>


int numRobot, numRow, numCol;
std::vector<std::vector<char>> data;
struct Pos{
	int row, col;
	int index() const{
		assert((unsigned) row<(unsigned) numRow); assert((unsigned) col<(unsigned) numCol);
		return col+numCol*row;
	}
};
struct State{
	int dir; // dir+1: clockwise
	int row, col;
	std::pair<int, int> dirVector() const{
		std::pair<int, int> result{1, 0};
		switch(dir){
			case 3: result={result.second,-result.first};
			case 2: result={result.second,-result.first};
			case 1: result={result.second,-result.first};
			case 0: return result;
		}
		assert(false);
	}

	int index() const{return dir+4*Pos{row, col}.index();}
};

int const loop=-2, uncomputed=-1;
std::vector<int> memory;

int compute(State it){
	auto& curMemory=memory[it.index()];
	if(curMemory!=uncomputed) return curMemory;

	State next=it;
	switch(data[next.row][next.col]){
		case 'A':
			next.dir=(next.dir-1)&3; break;
		case 'C':
			next.dir=(next.dir+1)&3; break;
		case 'x':
			assert(false); __builtin_unreachable();
	}
	next.row+=next.dirVector().first; next.col+=next.dirVector().second;

	if((unsigned)next.row>=(unsigned)numRow or (unsigned)next.col>=(unsigned)numCol or
			data[next.row][next.col]=='x')
		return curMemory=Pos{it.row, it.col}.index();

	curMemory=loop;
	return curMemory=compute(next);
}

int getMemory(int pos, int dir){
	int result=memory[dir+4*pos];
	assert(result!=uncomputed);
	return result;
}

int main(){
	std::ios::sync_with_stdio(0);std::cin.tie(0);
	std::cin>>numRobot>>numCol>>numRow;
	if(numRobot==1){std::cout<<"0\n"; return 0;}
	data.resize(numRow);
	for(auto& row: data){
		row.resize(numCol+1);
		std::cin>>row.data();
		assert(row.back()==0); row.pop_back();
		assert(row.back()!=0);
	}

	memory.assign(numRow*numCol*4, uncomputed);
	for(int row=0; row<numRow; ++row)
		for(int col=0; col<numCol; ++col)
			if(data[row][col]!='x')
				for(int dir=0; dir<4; ++dir){
					auto const result=compute({dir, row, col});
					(void) result;
					/*
					std::cerr<<row<<' '<<col<<' '<<dir<<'-'
						<<result/numCol<<' '<<result%numCol<<'\n';
						*/
				}

	int const numPos=numRow*numCol;
	std::vector<int> distance_(numPos*numRobot*numRobot, INT_MAX);
	auto const distance=[&](int a, int b, int pos)->int&{
		assert(0<=a); assert(a<=b); assert(b<numRobot);
		assert((unsigned)pos<unsigned(numPos));
		return distance_[a+numRobot*(b+numRobot*pos)];
	};

	struct State{
		char a, b; int pos;
	};
	std::vector<std::vector<State>> queue(numPos);
	auto const update=[&](int curDistance, int a, int b, int pos){
		if(curDistance<distance(a, b, pos)){
			while(curDistance>=(int)queue.size()) queue.resize(queue.size()*2);
			queue[distance(a, b, pos)=curDistance].push_back({(char) a, (char) b, pos});
		}
	};

	int result=INT_MAX;
	for(int a=numRobot; a--;){
		for(int row=0; row<numRow; ++row)
			for(int col=0; col<numCol; ++col){
				assert(distance(a, a, Pos{row, col}.index())==INT_MAX);
				if(data[row][col]==char('1'+a)){
					auto const pos=Pos{row, col}.index();
					update(0, a, a, pos);
				}
			}
	}

	for(int curDistance=0; curDistance<(int)queue.size(); ++curDistance){
		for(int index=0; index<(int)queue[curDistance].size(); ++index){
			auto [a, b, pos]=queue[curDistance][index];
			if(curDistance!=distance(a, b, pos)) continue;

			if(a==0 and b==numRobot-1){
				result=std::min(result, curDistance);
				continue;
			}

			for(int c=b+1; c<numRobot;++c){
				if(auto const d1=distance(b+1, c, pos); d1<=curDistance)
					update(curDistance+d1, a, c, pos);
			}
			for(int c=a; c--;){
				if(auto const d1=distance(c, a-1, pos); d1<=curDistance)
					update(curDistance+d1, c, b, pos);
			}

			for(int dir=0; dir<4; ++dir){
				auto const next=getMemory(pos, dir);
				if(next!=loop and distance(a, b, next)>curDistance+1){
					update(curDistance+1, a, b, next);
				}
			}
		}
	}
	std::cout<<(result==INT_MAX ? -1: result)<<'\n';
}

Compilation message

robots.cpp: In member function 'std::pair<int, int> State::dirVector() const':
robots.cpp:29:2: warning: control reaches end of non-void function [-Wreturn-type]
   29 |  }
      |  ^

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct

Subtask #3
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 244 ms 42616 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 21 ms 21504 KB Output is correct
14 Correct 582 ms 75512 KB Output is correct
15 Correct 92 ms 35956 KB Output is correct

Subtask #4
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 244 ms 42616 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 21 ms 21504 KB Output is correct
14 Correct 582 ms 75512 KB Output is correct
15 Correct 92 ms 35956 KB Output is correct
16 Correct 95 ms 89984 KB Output is correct
17 Runtime error 833 ms 163844 KB Execution killed with signal 9 (could be triggered by violating memory limits)
18 Halted 0 ms 0 KB -