Submission #260202

#	Time	Username	Problem	Language	Result	Execution time	Memory
260202		muhammad_hokimiyon	Lamps (JOI19_lamps)	C++14	100 / 100	82 ms	27820 KiB

lamp

#include <bits/stdc++.h>

//#pragma GCC optimize("Ofast")

#define fi first
#define se second
#define ll long long
#define dl double long

using namespace std;

const int NN = 1e9 + 7;
const int N = 1e6 + 1;
const int M = 2;
const ll mod = 1e9 + 7;
const int inf = 1e9 + 7;
const dl rf = 1e-14;
const int B = sqrt(N);
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

int n;
string s,t;
int d[N][3][2];

void upd( int &x , int y )
{
    x = min( x , y );
}

void solve1()
{
    cin >> n >> s >> t;
    s = '#' + s;
    t = '#' + t;
    for( int i = 0; i <= n; i++ ){
        for( int j = 0; j < 3; j++ ){
            for( int h = 0; h < 2; h++ ){
                d[i][j][h] = 1e9;
            }
        }
    }
    d[0][0][0] = 0;
    for( int i = 1; i <= n; i++ ){
        for( int j = 0; j < 3; j++ ){
            for( int h = 0; h < 2; h++ ){
                upd( d[i][j][h] , d[i - 1][j][h] );
                upd( d[i][0][h] , d[i - 1][j][h] );
                upd( d[i][j][0] , d[i - 1][j][h] );
                upd( d[i][0][0] , d[i - 1][j][h] );
                if( j == 0 ){
                    upd( d[i][1][h] , d[i - 1][j][h] + 1 );
                    upd( d[i][2][h] , d[i - 1][j][h] + 1 );
                    if( h == 0 ){
                        upd( d[i][1][1] , d[i - 1][j][h] + 2 );
                        upd( d[i][2][1] , d[i - 1][j][h] + 2 );
                    }
                }
                if( h == 0 ){
                    upd( d[i][j][1] , d[i - 1][j][h] + 1 );
                    upd( d[i][0][1] , d[i - 1][j][h] + 1 );
                }
            }
        }
        for( int j = 0; j < 3; j++ ){
            for( int h = 0; h < 2; h++ ){
                int a = s[i] - '0';
                int b = t[i] - '0';
                if( j == 1 )a = 0;
                else if( j == 2 )a = 1;
                if( h == 1 )a ^= 1;
                if( a != b ){
                    d[i][j][h] = 1e9;
                }
            }
        }
    }
    int res = 1e9;
    for( int i = 0; i < 3; i++ ){
        for( int h = 0; h < 2; h++ ){
            res = min( res , d[n][i][h] );
        }
    }
    cout << res;
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    //freopen( "input.txt" , "r" , stdin );
    //freopen( "output.txt" , "w" , stdout );

    int cghf = 1;//cin >> cghf;
    while( cghf-- ){
        solve1();
    }
}

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