Submission #607062

#	Time	Username	Problem	Language	Result	Execution time	Memory
607062		baoq06	Patkice II (COCI21_patkice2)	C++14	30 / 110	2084 ms	43408 KiB

Main

#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimization("unroll-loops")
#include<bits/stdc++.h>
using namespace std;

#define ll long long
#define all(x) x.begin(), x.end()
typedef pair<int, int> II;

template<typename T> bool maximize(T& a, T b) {return (a < b ? a = b, 1 : 0);}
template<typename T> bool minimize(T& a, T b) {return (a > b ? a = b, 1 : 0);}

const int INF = (int) 1e18;
const int MOD = 1e9 + 7;
const int N = 2e3 + 1;
const int dx[] = {-1, 0, 1, 0};
const int dy[] = {0, 1, 0, -1};

int n, m;
int xs, ys, xe, ye, d[N][N];
char a[N][N];

bool checkDir(const int &num, const char &dir)
{
	if(dir == '.') return 1;
	if(num == 0 && dir == '^') return 0;
	if(num == 1 && dir == '>') return 0;
	if(num == 2 && dir == 'v') return 0;
	if(num == 3 && dir == '<') return 0;
	return 1;
}

II trace[N][N];

void BFS()
{
	queue<II> Q;
	Q.push({xs, ys});
	d[xs][ys] = 0;
	
	while(Q.size())
	{
		auto cur = Q.front();
		Q.pop();
		
		if(a[cur.first][cur.second] == 'x') continue;
		
		for(int i = 0; i < 4; i++)
		{
			const int &X = cur.first + dx[i];
			const int &Y = cur.second + dy[i];
			
			if(X < 1 || X > n || Y < 1 || Y > m) continue;
			
			if(minimize(d[X][Y], d[cur.first][cur.second] + checkDir(i, a[cur.first][cur.second]))) 
			{
				trace[X][Y] = {cur.first, cur.second};
				Q.push({X, Y});
			}	
		}
	}
}

void Trace()
{
	II cur = {xe, ye};
	
	while(cur.first != xs || cur.second != ys)
	{
		II new_cur = trace[cur.first][cur.second];
		
		const int &X = new_cur.first;
		const int &Y = new_cur.second; 
		
		if(cur.first > X) a[X][Y] = 'v';
		else if(cur.first < X) a[X][Y] = '^';
		else if(cur.second < Y) a[X][Y] = '<';
		else a[X][Y] = '>';
		
		cur = new_cur;
	}
}

signed main() 
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

	memset(d, 0x3f, sizeof(d));

    scanf("%d%d", &n, &m);
    for(int i = 1; i <= n; i++) scanf("%s", a[i] + 1);

    for(int i = 1; i <= n; i++)
        for(int j = 1; j <= m; j++)
        {
            //cin >> a[i][j];
            if(a[i][j] == 'o') xs = i, ys = j;
            else if (a[i][j] == 'x') xe = i, ye = j;
        }
      
    BFS();
    Trace();
	
	printf("%d\n", d[xe][ye] - 1);
	
	a[xs][ys] = 'o';
	for(int i = 1; i <= n; i++) puts(a[i] + 1);
//	{
//		printf("%s", a[i] + 1);
//		printf("\n");
//	}

    return 0;
}

Compilation message (stderr)

Main.cpp:3: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
    3 | #pragma GCC optimization("unroll-loops")
      | 
Main.cpp: In function 'int main()':
Main.cpp:92:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   92 |     scanf("%d%d", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~
Main.cpp:93:38: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   93 |     for(int i = 1; i <= n; i++) scanf("%s", a[i] + 1);
      |                                 ~~~~~^~~~~~~~~~~~~~~~

• Subtask 1: 30 / 30
• Subtask 2: 0 / 80