oj.uz

Submission #262852

# Submission time Handle Problem Language Result Execution time Memory
262852 2020-08-13T10:05:07 Z user202729 Robots (APIO13_robots) C++17
60 / 100
 1029 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)];
	};

	std::vector<std::vector<int>> queue(numPos*numRobot*7/8+20);

	int result=INT_MAX;
	for(int a=numRobot; a--;){
		for(int b=a; b<numRobot; ++b){
			struct State{
				int pos, distance;
				bool operator<(State it) const{return distance>it.distance;}
			};

			int minDistance=INT_MAX, maxDistance=0;
			if(a==b){
				//for(int pos=0; pos<numPos; ++pos)
				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();
							queue[distance(a, a, pos)=0].push_back(pos);
							minDistance=0;
						}
					}
			}else{
				for(int pos=0; pos<numPos; ++pos){
					unsigned t=INT_MAX;
					for(int m=a; m<b; ++m)
						t=std::min(t, (unsigned)distance(a, m, pos)+
								distance(m+1, b, pos));
					assert(distance(a, b, pos)==INT_MAX);
					if(t<INT_MAX){
						if(b==numRobot-1 and a==0)
							result=std::min(result, (int)t);
						else{
							queue[distance(a, b, pos)=t].push_back(pos);
							minDistance=std::min(minDistance, (int)t);
							maxDistance=std::max(maxDistance, (int)t);
						}
					}
				}
			}

			for(int curDistance=minDistance; curDistance<=maxDistance; ++curDistance){
				for(auto pos: queue[curDistance]){
					if(curDistance!=distance(a, b, pos)) continue;
					for(int dir=0; dir<4; ++dir){
						auto const next=getMemory(pos, dir);
						if(next!=loop and distance(a, b, next)>curDistance+1){
							queue[distance(a, b, next)=curDistance+1].push_back(next);
							maxDistance=std::max(maxDistance, curDistance+1);
						}
					}
				}
			}
		}
	}
	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 0 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 0 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 0 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 0 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 0 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 0 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 337 ms 51532 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 68 ms 32252 KB Output is correct
14 Correct 478 ms 65304 KB Output is correct
15 Correct 171 ms 48760 KB Output is correct

Subtask #4
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 0 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 337 ms 51532 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 68 ms 32252 KB Output is correct
14 Correct 478 ms 65304 KB Output is correct
15 Correct 171 ms 48760 KB Output is correct
16 Correct 372 ms 130296 KB Output is correct
17 Runtime error 1029 ms 163844 KB Execution killed with signal 9 (could be triggered by violating memory limits)
18 Halted 0 ms 0 KB -