Submission #637266

#	Time	Username	Problem	Language	Result	Execution time	Memory
637266		Fidan	Thousands Islands (IOI22_islands)	C++17	Compilation error	0 ms	0 KiB

islands

#include <bits/stdc++.h>
#include <variant>
#include "islands.h"
using namespace std;
typedef int ll;
variant<bool, vector<int>> find_journey(int n, int m, vector<int> u, vector<int> v){
	if(n==2){
		ll a=-1, b=-1, c=-1;
		for(ll i=0; i<m; i++){
			if(u[i]==0){
				if(a==-1) a=i;
				else b=i;
			}
			else c=i;
		}
		if(b==-1 || c==-1) return false;
		return vector<int>({a, c, b, a, c, b});
	}
	else if(m==n*(n-1)){
		ll a=-1, b=-1, c=-1, d=-1, e=-1, f=-1;
		for(ll i=0; i<m; i++){
			if(u[i]==0 && v[i]==1) a=i;
			if(u[i]==1 && v[i]==0) b=i;
			if(u[i]==1 && v[i]==2) c=i;
			if(u[i]==2 && v[i]==1) d=i;
			if(u[i]==2 && v[i]==0) e=i;
			if(u[i]==0 && v[i]==2) f=i;
		}
		return vector<int>({a, c, e, f, d, b, e, c, a, b, d, f});
	}
	else{
		vector<vector<pair<ll, ll>>> v(n);
		for(ll i=0; i<m; i++){
			v[u[i]].push_back({v[i], i});
		}
		if(v[0].size()==2){
			ll a=v[0][0].second, b=v[0][1].second;
			ll a1, b1;
			if(a%2==0) a1=a+1;
			else a1=a-1;
			if(b%2==0) b1=b+1;
			else b1=b-1;
			return vector<int>({a, a1, b, b1, a1, a, b1, b});
		}
		else{
			bool f=false;
			for(ll i=0; i<n; i++){
				if(v[i].size()>=3) f=true;
			}
			if(!f) return false;
			vector<ll> res1, res;
			res1.push_back(v[0][0].second);
			ll l=v[0][0].first, k=0;
			while(v[l].size()<3){
				if(v[l][0].first==k){
					res1.push_back(v[l][1].second);
					res.push_back(v[l][1].second);
					k=l;
					l=v[l][1].first;
				}
				else{
					res1.push_back(v[l][0].second);
					res.push_back(v[l][0].second);
					k=l;
					l=v[l][0].first;
				}
			}
			ll a=-1, b=-1;
			for(ll i=0; i<v[l].size(); i++){
				if(v[l][i].first!=k){
					if(a==-1) a=v[l][i].second;
					else b=v[l][i].second;
				}
			}
			ll a1, b1;
			if(a%2==0) a1=a+1;
			else a1=a-1;
			if(b%2==0) b1=b+1;
			else b1=b-1;
			res.push_back(a);
			res.push_back(a1);
			res.push_back(b);
			res.push_back(b1);
			res.push_back(a1);
			res.push_back(a);
			res.push_back(b1);
			res.push_back(b);
			reverse(res1.begin(), res1.end());
			for(ll asdf:res1) res.push_back(asdf);
			return res;
		}
	}
}

Compilation message (stderr)

islands.cpp: In function 'std::variant<bool, std::vector<int, std::allocator<int> > > find_journey(int, int, std::vector<int>, std::vector<int>)':
islands.cpp:34:31: error: no matching function for call to 'std::vector<std::pair<int, int> >::push_back(<brace-enclosed initializer list>)'
   34 |    v[u[i]].push_back({v[i], i});
      |                               ^
In file included from /usr/include/c++/10/vector:67,
                 from /usr/include/c++/10/functional:62,
                 from /usr/include/c++/10/pstl/glue_algorithm_defs.h:13,
                 from /usr/include/c++/10/algorithm:74,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:65,
                 from islands.cpp:1:
/usr/include/c++/10/bits/stl_vector.h:1187:7: note: candidate: 'void std::vector<_Tp, _Alloc>::push_back(const value_type&) [with _Tp = std::pair<int, int>; _Alloc = std::allocator<std::pair<int, int> >; std::vector<_Tp, _Alloc>::value_type = std::pair<int, int>]'
 1187 |       push_back(const value_type& __x)
      |       ^~~~~~~~~
/usr/include/c++/10/bits/stl_vector.h:1187:35: note:   no known conversion for argument 1 from '<brace-enclosed initializer list>' to 'const value_type&' {aka 'const std::pair<int, int>&'}
 1187 |       push_back(const value_type& __x)
      |                 ~~~~~~~~~~~~~~~~~~^~~
/usr/include/c++/10/bits/stl_vector.h:1203:7: note: candidate: 'void std::vector<_Tp, _Alloc>::push_back(std::vector<_Tp, _Alloc>::value_type&&) [with _Tp = std::pair<int, int>; _Alloc = std::allocator<std::pair<int, int> >; std::vector<_Tp, _Alloc>::value_type = std::pair<int, int>]'
 1203 |       push_back(value_type&& __x)
      |       ^~~~~~~~~
/usr/include/c++/10/bits/stl_vector.h:1203:30: note:   no known conversion for argument 1 from '<brace-enclosed initializer list>' to 'std::vector<std::pair<int, int> >::value_type&&' {aka 'std::pair<int, int>&&'}
 1203 |       push_back(value_type&& __x)
      |                 ~~~~~~~~~~~~~^~~
islands.cpp:69:17: warning: comparison of integer expressions of different signedness: 'll' {aka 'int'} and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   69 |    for(ll i=0; i<v[l].size(); i++){
      |                ~^~~~~~~~~~~~