Submission #30707

#	Time	Username	Problem	Language	Result	Execution time	Memory
30707		zscoder	Match (CEOI16_match)	C++14	10 / 100	0 ms	3316 KiB

match

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
 
using namespace std;
using namespace __gnu_pbds;
 
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define fbo find_by_order
#define ook order_of_key
 
typedef long long ll;
typedef pair<int,ll> ii;
typedef vector<int> vi;
typedef long double ld; 
typedef tree<ll, null_type, less<ll>, rb_tree_tag, tree_order_statistics_node_update> pbds;
typedef set<ll>::iterator sit;
typedef map<ll,ll>::iterator mit;
 
bool err;

string solve(string &s)
{
	if(s.empty()) return "";
	int n = s.length();
	stack<char> S;
	string ans;
	int idx=-1;
	if(s[0]==s[n-1])
	{
		string s2 = s.substr(1,int(s.length()) - 2);
		s2=solve(s2);
		if(err) return "";
		return "("+s2+")";
	}
	for(int i = n - 1; i > 0; i--)
	{
		if(!S.empty()&&S.top()==s[i])
		{
			S.pop();
		}
		else
		{
			S.push(s[i]);
		}
		if(s[0]==s[i-1]&&S.empty())
		{
			idx=i;
			break;
		}
	}
	if(idx<=0)
	{
		err=true;
		return "";
	}
	string l = s.substr(1,idx-2);
	string r = s.substr(idx,int(s.length()) - idx);
	l = solve(l);
	if(err) return "";
	r = solve(r);
	if(err) return "";
	return "("+l+")"+r;
}

int main()
{
	ios_base::sync_with_stdio(0); cin.tie(0);
	string s; cin>>s;
	int n=s.length();
	/*
	for(int i=0;i<n;i++)
	{
		stack<char> S;
		for(int j=i;j<n;j++)
		{
			if(!S.empty()&&S.top()==s[j])
			{
				S.pop();
			}
			else S.push(s[j]);
			if(S.empty()) 
			{
				//cerr<<i<<' '<<j<<'\n';
				dp[i][j]=1;
			}
		}
	}
	*/
	string ans = solve(s);
	if(err) cout<<-1<<'\n';
	else cout<<ans<<'\n';	
}

Compilation message (stderr)

match.cpp: In function 'int main()':
match.cpp:73:6: warning: unused variable 'n' [-Wunused-variable]
  int n=s.length();
      ^

• Subtask 1: 10 / 10
• Subtask 2: 0 / 27
• Subtask 3: 0 / 63