Submission #707017

#	Time	Username	Problem	Language	Result	Execution time	Memory
707017		Antekb	Lamps (JOI19_lamps)	C++14	100 / 100	36 ms	31308 KiB

lamp

#include<bits/stdc++.h>
 
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("trapv")
 
#define st first
#define nd second
#define pb push_back
#define eb emplace_back
#define pp(x) pop_back(x)
#define mp(a, b) make_pair(a, b)
#define all(x) (x).begin(), (x).end()
#define rev(x) reverse(all(x))
#define sor(x) sort(all(x))
#define sz(x) (int)(x).size()
#define rsz(x) resize(x)
 
using namespace std;
 
///~~~~~~~~~~~~~~~~~~~~~~~~~~
 
template <typename H, typename T> 
ostream& operator<<(ostream& os, pair<H, T> m){
	return os <<"("<< m.st<<", "<<m.nd<<")";
}
template <typename H> 
ostream& operator<<(ostream& os, vector<H> V){
	os<<"{";
	for(int i=0; i<V.size(); i++){
		if(i)os<<" ";
		os<<V[i];
	}
	os<<"}";
	return os;
}
 
void debug(){cerr<<"\n";}
template <typename H, typename... T>
void debug(H h, T... t) {cerr<<h; if (sizeof...(t)) cerr << ", "; debug(t...);}
#define deb(x...) cerr<<#x<<" = ";debug(x);
//#define deb(x...) ;
 
///~~~~~~~~~~~~~~~~~~~~~~~~~
 
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii > vii;
typedef vector<ll> vl;
typedef vector<pll> vll;
typedef string str;

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
template <typename T>
using ordered_set =
    tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

 
#define BOOST ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
 
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
 
const int K=20, N=1<<K, INF=1e9+5, mod2=1e9+7, mod=998244353;

struct modint{
	int n=0;
	modint(){}
	modint(ll x){
		n=x%mod;
		if(n<0)n+=mod;
	}
	operator int(){
		return n;
	}
	modint operator+(modint a){a.n = n+a.n; if(a.n>=mod)a.n-=mod;return a;}
	modint operator+=(modint a){return (*this)=(*this)+a;}
	modint operator-(modint a){a.n = n-a.n; if(a.n<0)a.n+=mod;return a;}
	modint operator-=(modint a){return (*this)=(*this)-a;}
	modint operator*(modint a){a.n = (n*1ll*a.n)%mod; return a;}
	modint operator*=(modint a){return (*this)=(*this)*a;}
	modint operator^(const ll &m)const{
		modint a(1);
		if(m==0)return a;
		if(m==1)return (*this);
		a=(*this)^(m/2);
		a*=a;
		return a*((*this)^(m&1));
	}
	modint odw(){
		return (*this)^((ll)mod-2);
	}
	modint operator/(modint a){return (*this)*a.odw();}
	modint operator/=(modint a){return (*this)=(*this)/a;}
	bool operator==(modint a){return a.n==n;}
	friend ostream& operator<<(ostream& os, modint m) {
		return os << m.n; 
	}
};
modint fact[N], fact2[N];
typedef vector<modint> vm;
void factinit(){
    fact[0]=1;
    for(int i=1; i<N; i++){
        fact[i]=(fact[i-1]*modint(i))%mod;
    }
    fact2[N-1]=fact[N-1].odw();
    for(int i=N-2; i>=0; i--){
    	fact2[i]=(fact2[i+1]*modint(i+1))%mod;
    }
}
modint npok(int _n, int _k){
    return fact[_n]*fact2[_k]*fact2[_n-_k];
}
int A[N], B[N], dp[N][3];
int main(){
	//factinit();
	BOOST;
	int n;
	cin>>n;
	string s;
	cin>>s;
	for(int i=0; i<n; i++)A[i+1]=s[i]&1;
	cin>>s;
	for(int i=0; i<n; i++)B[i+1]=s[i]&1;
	dp[0][0]=dp[0][1]=INF;
	for(int i=1; i<=n+1; i++){
		for(int j=0; j<3; j++){
			dp[i][j]=INF;
			for(int k=0; k<3; k++){
				int c=0;
				if(j!=2 && k!=j)c=2;
				int a=A[i-1], b=A[i];
				if(j!=2)b=j;
				if(k!=2)a=k;
				a^=B[i-1];
				b^=B[i];
				dp[i][j]=min(dp[i][j], dp[i-1][k]+c+(a^b));
			}
		}
	}
	cout<<dp[n+1][2]/2;
}

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