Submission #250678

#	Time	Username	Problem	Language	Result	Execution time	Memory
250678		Blagojce	Lamps (JOI19_lamps)	C++11	100 / 100	50 ms	27988 KiB

lamp

#include <bits/stdc++.h> 
#define fr(i, n, m) for(int i = (n); i < (m); i ++)
#define pb push_back
#define st first
#define nd second
#define pq priority_queue
#define all(x) begin(x), end(x)
#include <time.h>
#include <cmath>

using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;

const int i_inf = 1e9;
const ll inf = 1e18;
const ll mod = 1000000007;
const ld eps = 1e-13;
const ld pi  = 3.14159265359;
 
mt19937 _rand(time(NULL));
clock_t timer = clock();
const int mxn = 4e6;
 
const ll A = 911382323;
const ll B = 972663749;
 
ll modpow(ll x, ll n){
	if(n == 0) return 1%mod;
	ll u = modpow(x, n/2);
	u = (u * u) % mod;
	if(n % 2) u = (u * x) % mod;
	return u;
}
ll inverse(ll x){
	return modpow(x, mod-2);
}
ll add(ll ans, ll val){
	ans = (ans + val) % mod;
	return ans;
}
ll mul(ll ans, ll val){
	ans = (ans * val) % mod;
	return ans;
}
ll sub(ll ans, ll val){
	ans = (ans - val) % mod;
	if(ans < 0) ans += mod;
	return ans;
}
ll _div(ll ans, ll val){
	ans = (ans * inverse(val)) % mod;
	return ans;
}
ll fakt[mxn];
ll bc(ll n, ll k){
	return (fakt[n]*inverse((fakt[k]*fakt[n-k])%mod))%mod;
}
ll sq(ll x){
	return x*x;
}
ll rsum(ll a, ll b){
	return (b-a+1)*(a+b)/2;
}
void prec(){
	fakt[0] = 1;
	fr(i, 1, mxn){
		fakt[i] = mul(fakt[i-1], i);
	}
}


int dp[mxn][6];
int trans[6][6];

void solve(){
	int val[6] = {0, 1, 2, 4, 5, 6};
	fr(i, 0, 6) fr(j, 0, 6) trans[i][j] = __builtin_popcount((val[i]|val[j])^val[i]);
		
	int n;
	cin >> n;
	string a, b;
	cin >> a;
	cin >> b;
	fr(i, 0, n+1)fr(j, 0, 6) dp[i][j] = i_inf;
	dp[0][0] = 0;
	
	fr(i, 1, n+1){
		if(a[i-1] == '1' && b[i-1] == '1'){
			fr(pr, 0, 6){
				dp[i][0] = min(dp[i][0], dp[i-1][pr] + trans[pr][0]); 
				dp[i][1] = min(dp[i][1], dp[i-1][pr] + trans[pr][1]);
				dp[i][5] = min(dp[i][5], dp[i-1][pr] + trans[pr][5]);
			}
		}
		else if(a[i-1] == '0' && b[i-1] == '0'){
			fr(pr, 0, 6){
				dp[i][0] = min(dp[i][0], dp[i-1][pr] + trans[pr][0]); 
				dp[i][2] = min(dp[i][2], dp[i-1][pr] + trans[pr][2]);
				dp[i][4] = min(dp[i][4], dp[i-1][pr] + trans[pr][4]);
			}
		}
		else if(a[i-1] == '1' && b[i-1] == '0'){
			fr(pr, 0, 6){
				dp[i][2] = min(dp[i][2], dp[i-1][pr] + trans[pr][2]); 
				dp[i][3] = min(dp[i][3], dp[i-1][pr] + trans[pr][3]);
				dp[i][4] = min(dp[i][4], dp[i-1][pr] + trans[pr][4]);
			}
		}
		else if(a[i-1] == '0' && b[i-1] == '1'){
			fr(pr, 0, 6){
				dp[i][1] = min(dp[i][1], dp[i-1][pr] + trans[pr][1]); 
				dp[i][3] = min(dp[i][3], dp[i-1][pr] + trans[pr][3]);
				dp[i][5] = min(dp[i][5], dp[i-1][pr] + trans[pr][5]);
			}
		}
	}
	
	int ans = i_inf;
	fr(i, 0, 6) ans = min(ans, dp[n][i]);
	cout<<ans<<endl;
	
	
	
}
 
int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	solve();
}

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