Submission #1751852


Source Code Expand

#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,int> ii;
typedef vector<int> vi;
typedef long double ld; 
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> pbds;
typedef set<int>::iterator sit;
typedef map<int,int>::iterator mit;
typedef vector<int>::iterator vit;

int solve(string &s1, string &s2)
{
	int n=s1.length();
	int ans=0;
	int ptr=n-1;
	vector<ii> vec;
	for(int i=n-1;i>=0;i--)
	{
		if(s1[ptr]==s2[i])
		{
			if(ptr==i)
			{
				ptr--;
			}
			continue;
		}
		ptr--;
		while(ptr>=0)
		{
			if(s1[ptr]==s2[i])
			{
				break;
			}
			ptr--;
		}
		if(ptr<0)
		{
			return -1;
		}
		vec.pb(mp(ptr,i));
	}
	int C = 0;
	vi L; deque<int> R;
	for(int i=0;i<n;i++) L.pb(0);
	for(int i=0;i<vec.size();i++)
	{
		int l=vec[i].fi; int r=vec[i].se;
		while(L.size()+R.size()>r+1)
		{
			if(!R.empty()) 
			{
				ans=max(ans,R.back()+C); R.pop_back();
			}
			else
			{
				ans=max(ans,L.back()); L.pop_back();
			}
		}
		//element l must be in L. pick r - l + 1 - R.size() elements from left side
		for(int i=int(L.size()) - 1; i > int(L.size()) - (r - l + 1 - int(R.size())); i--)
		{
			R.push_front(L.back()-C);
			L.pop_back();
		}
		L.pop_back();
		R.pb(R.back());
		C++;
	}
	for(int i=0;i<L.size();i++) ans=max(ans,L[i]);
	for(int i=0;i<R.size();i++) ans=max(ans,R[i]+C);
	return ans;
}

int main()
{
	ios_base::sync_with_stdio(0); cin.tie(0);
	int n; string s1,s2;
	cin>>n>>s1>>s2;
	cout<<solve(s1,s2)<<'\n';
}

Submission Info

Submission Time
Task F - Shik and Copying String
User vjudge5
Language C++14 (GCC 5.4.1)
Score 1500
Code Size 1729 Byte
Status AC
Exec Time 38 ms
Memory 18064 KB

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 1500 / 1500
Status
AC × 4
AC × 63
Set Name Test Cases
Sample example0.txt, example1.txt, example2.txt, example3.txt
All 000.txt, 001.txt, 002.txt, 003.txt, 004.txt, 005.txt, 006.txt, 007.txt, 008.txt, 009.txt, 010.txt, 011.txt, 012.txt, 013.txt, 014.txt, 015.txt, 016.txt, 017.txt, 018.txt, 019.txt, 020.txt, 021.txt, 022.txt, 023.txt, 024.txt, 025.txt, 026.txt, 027.txt, 028.txt, 029.txt, 030.txt, 031.txt, 032.txt, 033.txt, 034.txt, 035.txt, 036.txt, 037.txt, 038.txt, 039.txt, 040.txt, 041.txt, 042.txt, 043.txt, 044.txt, 045.txt, 046.txt, 047.txt, 048.txt, 049.txt, 050.txt, 051.txt, 052.txt, 053.txt, 054.txt, 055.txt, 056.txt, 057.txt, 058.txt, example0.txt, example1.txt, example2.txt, example3.txt
Case Name Status Exec Time Memory
000.txt AC 1 ms 256 KB
001.txt AC 1 ms 256 KB
002.txt AC 1 ms 256 KB
003.txt AC 1 ms 256 KB
004.txt AC 1 ms 256 KB
005.txt AC 1 ms 256 KB
006.txt AC 1 ms 256 KB
007.txt AC 1 ms 256 KB
008.txt AC 1 ms 256 KB
009.txt AC 1 ms 256 KB
010.txt AC 1 ms 256 KB
011.txt AC 1 ms 256 KB
012.txt AC 1 ms 256 KB
013.txt AC 1 ms 256 KB
014.txt AC 1 ms 256 KB
015.txt AC 1 ms 256 KB
016.txt AC 1 ms 256 KB
017.txt AC 1 ms 256 KB
018.txt AC 1 ms 256 KB
019.txt AC 1 ms 256 KB
020.txt AC 1 ms 256 KB
021.txt AC 1 ms 256 KB
022.txt AC 1 ms 256 KB
023.txt AC 1 ms 256 KB
024.txt AC 1 ms 256 KB
025.txt AC 11 ms 7448 KB
026.txt AC 32 ms 18064 KB
027.txt AC 25 ms 13844 KB
028.txt AC 38 ms 17424 KB
029.txt AC 38 ms 16016 KB
030.txt AC 16 ms 8344 KB
031.txt AC 18 ms 9624 KB
032.txt AC 20 ms 9496 KB
033.txt AC 21 ms 9752 KB
034.txt AC 22 ms 9880 KB
035.txt AC 22 ms 8984 KB
036.txt AC 22 ms 9752 KB
037.txt AC 21 ms 8856 KB
038.txt AC 21 ms 8088 KB
039.txt AC 20 ms 8344 KB
040.txt AC 34 ms 15120 KB
041.txt AC 33 ms 18064 KB
042.txt AC 31 ms 17680 KB
043.txt AC 31 ms 18064 KB
044.txt AC 31 ms 18064 KB
045.txt AC 31 ms 18064 KB
046.txt AC 31 ms 18064 KB
047.txt AC 32 ms 18064 KB
048.txt AC 31 ms 18064 KB
049.txt AC 31 ms 18064 KB
050.txt AC 18 ms 12436 KB
051.txt AC 17 ms 11796 KB
052.txt AC 12 ms 8216 KB
053.txt AC 29 ms 14100 KB
054.txt AC 28 ms 12948 KB
055.txt AC 29 ms 12820 KB
056.txt AC 30 ms 14484 KB
057.txt AC 28 ms 12436 KB
058.txt AC 36 ms 13972 KB
example0.txt AC 1 ms 256 KB
example1.txt AC 1 ms 256 KB
example2.txt AC 1 ms 256 KB
example3.txt AC 1 ms 256 KB