제출 #210832

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
210832		amiratou	Lamps (JOI19_lamps)	C++14	4 / 100	50 ms	16200 KiB

lamp

#pragma GCC optimize("O3")
#include <bits/stdc++.h>
using namespace std;
#define boost ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)
#define rando mt19937 rng(chrono::steady_clock::now().time_since_epoch().count())
#define fi first
#define se second
#define debug(x) cerr << " - " << #x << ": " << x << endl;
#define debugs(x, y) cerr << " - " << #x << ": " << x << " " << #y << ": " << y << endl;
#define debugii(x) cerr << " - " << #x << ": " << x.fi<<","<<x.se << endl;
#define sep() cerr << "--------------------" << endl;
#define all(x) (x).begin(),(x).end()
#define sz(x) (ll)x.size()
#define ld long double
#define ll long long
//#define int ll
#define ii pair<int,int>
#define v vector<int>
#define vii vector<ii>
#define vv vector<vector<int> >
#define mp make_pair
#define INF 1000000000
#define pb push_back
#define EPS 1e-9
const int MOD = 1000000007; // 998244353
int t[1000002],pre[1000002],dp[1000002];
int n;
string A,B;
void pro(){
	for (int i = n-1; i >= 0; i--)
	{
		int h=(int)(A[i]-'0')^(int)(B[i]-'0');
		if(!h)t[i]=-1;
		else if(i==(n-1)||t[i+1]==-1)t[i]=i;
		else t[i]=t[i+1];
		if(i==(n-1)||(B[i]!=B[i+1]))pre[i]=i;
		else pre[i]=pre[i+1];
		dp[i+1]=INF;
	}
}
int solve(){
	dp[0]=0;
	for (int i = 0; i < n; ++i)
	{
		if(A[i]==B[i])dp[i+1]=min(dp[i+1],dp[i]);
		else{
			dp[t[i]+1]=min(dp[t[i]+1],dp[i]+1);
			dp[pre[i]+1]=min(dp[pre[i]+1],dp[i]+1);
		}
	}
	return dp[n];
}
int32_t main(){
	boost;
	//freopen(".in","r",stdin);
	cin>>n;
	cin>>A>>B;
	pro();
	int ans=solve();
	for (int i = 0; i < n; ++i)
		A[i]=(char)(1-(int)(A[i]-'0')+'0'),pre[i]=t[i]=0;
	pro();
	cout<<min(ans,solve()+1);
	return 0;
}
//long long
//array bounds
//special cases
//binary search

• Subtask 1: 0 / 6
• Subtask 2: 0 / 41
• Subtask 3: 4 / 4
• Subtask 4: 0 / 49