Submission #498358

#	Time	Username	Problem	Language	Result	Execution time	Memory
498358		mansur	Robots (APIO13_robots)	C++17	30 / 100	324 ms	46032 KiB

robots

#include<bits/stdc++.h>	
/* 
#pragma optimize ("g",on)
#pragma GCC optimize ("inline")
#pragma GCC optimize ("Ofast")
#pragma GCC optimize ("unroll-loops")
#pragma GCC optimize ("03")
#pragma GCC target ("sse,sse2,sse3,ssse3,sse4,popcnt,abm,avx2,mmx,fma,avx,tune=native")
#pragma comment(linker, "/stack:200000000")
*/ 
//01001101 01100001 01101011 01101000 01100001  01100111 01100001 01111001 
 
using namespace std;
 
#define all(a) a.begin(), a.end()                                                   
#define rall(a) a.rbegin(), a.rend()
#define ll long long
#define pb push_back
#define sz(a) a.size()
#define nl '\n'
#define popb pop_back()                                                                   
#define ld double
#define ull unsigned long long
#define ff first                                         
#define ss second  
#define fix fixed << setprecision
#define pii pair<int, int>                          
#define E exit (0)
#define int long long
 
const int inf = 1e15, N = 3e5 + 5, mod = 998244353;                    
 
vector<pii> dir = {{1, 0}, {0, 1}, {-1, 0}, {0, -1}};

int d1[301][301], d2[301][301];

char c[301][301];

int n, m;

map<pii, int> was1[4], was2[4];

pii dfs1(pii pos, int d, int dst) {
	if (c[pos.ff][pos.ss] == 'A') d = (d + 1) % 4;
	if (c[pos.ff][pos.ss] == 'C') d = (d + 3) % 4;
	if (was1[d][pos] <= dst) {
		return {-1, -1};	
	}
	was1[d][pos] = dst;
	pii p = pos;
	p.ff += dir[d].ff;
	p.ss += dir[d].ss;
	if (p.ff > n || p.ss > m || p.ff < 1 || p.ss < 1 || c[p.ff][p.ss] == 'x') {
    	d1[pos.ff][pos.ss] = min(d1[pos.ff][pos.ss], dst);
    	return pos;
    }
	return dfs1(p, d, dst);
}

pii dfs2(pii pos, int d, int dst) {
	if (c[pos.ff][pos.ss] == 'A') d = (d + 1) % 4;
	if (c[pos.ff][pos.ss] == 'C') d = (d + 3) % 4;
	if (was2[d][pos] <= dst) {
		return {-1, -1};	
	}
	was2[d][pos] = dst;
	pii p = pos;
	p.ff += dir[d].ff;
	p.ss += dir[d].ss;
	if (p.ff > n || p.ss > m || p.ff < 1 || p.ss < 1 || c[p.ff][p.ss] == 'x') {
    	d2[pos.ff][pos.ss] = min(d2[pos.ff][pos.ss], dst);
    	return pos;
    }
	return dfs2(p, d, dst);
}

main() {                                                         
	//freopen("triangles.in", "r", stdin);                                                                                     
	//freopen("triangles.out", "w", stdout);                                                                                     
	ios_base::sync_with_stdio(NULL);                                                                                        
	cin.tie(NULL);
	int x;
	cin >> x >> m >> n;
	pii pos1, pos2; 
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) {
			cin >> c[i][j];
			was1[0][{i, j}] = inf, was2[0][{i, j}] = inf;
			was1[1][{i, j}] = inf, was2[1][{i, j}] = inf;
			was1[2][{i, j}] = inf, was2[2][{i, j}] = inf;
			was1[3][{i, j}] = inf, was2[3][{i, j}] = inf;
			d1[i][j] = d2[i][j] = inf;
			if (c[i][j] == '1') pos1 = {i, j};
			if (c[i][j] == '2') pos2 = {i, j};
		}
	}
	queue<pii> q;
	q.push(pos1);
	d1[pos1.ff][pos1.ss] = 0;
	while (!q.empty()) {
	    pii cur = q.front();
	    q.pop();
	    for (int i = 0; i < 4; i++) {
	    	pii a = dfs1(cur, i, d1[cur.ff][cur.ss] + 1);
	    	if (a.ff != -1) {
	    		q.push(a);
	    	}
	    }
    }
	q.push(pos2);
	d2[pos2.ff][pos2.ss] = 0;
	while (!q.empty()) {
	    pii cur = q.front();
	    q.pop();
	    for (int i = 0; i < 4; i++) {
	    	pii a = dfs2(cur, i, d2[cur.ff][cur.ss] + 1);
	    	if (a.ff != -1) {
	    		q.push(a);
	    	}
	    }
    }	  
	int mn = inf;
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= m; j++) mn = min(mn, d1[i][j] + d2[i][j]);
	}
	if (mn == inf) mn = -1;
	cout << mn;
}

Compilation message (stderr)

robots.cpp:77:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   77 | main() {
      | ^~~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 0 / 30
• Subtask 4: 0 / 40