Submission #543516

#	Time	Username	Problem	Language	Result	Execution time	Memory
543516		brunnorezendes	Fountain Parks (IOI21_parks)	C++17	Compilation error	0 ms	0 KiB

parks

#include <bits/stdc++.h>
#define s second
#define f first

using namespace std;

typedef vector <int> vi;
typedef pair<int, int> ii;
typedef pair<ii, ii> iiii;
typedef vector<ii> vii;
typedef map <pair<int,int>, int > mpair;

mpair mp,  match1;
vi u, v, a, b;
vii match2;

iiii find(int t, vi x, vi y){
	ii c, d;
	iiii e;
	int i = u[t], j = v[t];
	if(x[i]==x[j]){
		c = {x[i]+1, (y[i]+y[j])/2};
		d = {x[i]-1, (y[i]+y[j])/2};
		e = {c, d};
		return (e);
	}
	else{
		c = {(x[i]+x[j])/2, y[i]+1};
		d = {(x[i]+x[j])/2, y[i]-1};
		e = {c, d};
		return (e);
	}
}

int matching(int t, vi x, vi y){
	iiii retur;
	ii op1, op2;
	retur = find(t, x, y);
	op1 = retur.f;
	op2 = retur.s;
	if(!match1[op1]){
		match1[op1] = t+1;
		match2[t] = op1;
		return 1;
	}
	else if(!match1[op2]){
		match1[op2] = t+1;
		match2[t] = op2;
		return 1;
	}
	else{
		if((match1[op1] != t+1) && (match1[op2] != t+1)){
			return 0;
		}
		if(match1[op2]==t+1) swap(op1, op2);
		if(matching(match1[op2]-1, x, y)){
			match1[op2] = t+1;
			match2[t] = op2;
			return 1;
		}
	}
}

int maskx[4], masky[4];

int construct_roads(vi x, vi y){
	maskx[1] = 2; maskx[3] = -2;
	masky[0] = 2; masky[2] = -2;
	int n = x.size(), i, f, j;
	match2 = vii(n, {-1, -1});
	for(i=0;i<n;i++){
		mp[{x[i], y[i]}] = i+1;
	}
	for(i=0;i<n;i++){
		for(j=0;j<4;j++){
			f = mp[{x[i]+maskx[j], y[i]+masky[j]}];
			if(f>i+1){
				f--;
				u.push_back(i);
				v.push_back(f);
			}
		}
	}
	for(i=0;i<u.size();i++){
		if(!matching(i, x, y)) return 0;
	}
	for(i=0;i<u.size();i++){
		a.push_back(match2[i].f);
		b.push_back(match2[i].s);
	}
	build(u, v, a, b);
	return 1;
}

Compilation message (stderr)

parks.cpp: In function 'int construct_roads(vi, vi)':
parks.cpp:84:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   84 |  for(i=0;i<u.size();i++){
      |          ~^~~~~~~~~
parks.cpp:87:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   87 |  for(i=0;i<u.size();i++){
      |          ~^~~~~~~~~
parks.cpp:91:2: error: 'build' was not declared in this scope
   91 |  build(u, v, a, b);
      |  ^~~~~
parks.cpp: In function 'int matching(int, vi, vi)':
parks.cpp:62:1: warning: control reaches end of non-void function [-Wreturn-type]
   62 | }
      | ^