Submission #302247

#	Time	Username	Problem	Language	Result	Execution time	Memory
302247		NaimSS	Lamps (JOI19_lamps)	C++14	0 / 100	276 ms	262144 KiB

lamp

#include <bits/stdc++.h>
#define ld long double
#define endl "\n"
#define fastio ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define pb(x) push_back(x)
#define mp(a,b) make_pair(a,b)
#define ms(v,x) memset(v,x,sizeof(v))
#define all(v) v.begin(),v.end()
#define ff first
#define ss second
#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define per(i, a, b) for(int i = b-1; i>=a ; i--)
#define trav(a, x) for(auto& a : x)
#define allin(a , x) for(auto a : x)
#define Unique(v) sort(all(v));v.erase(unique(all(v)),v.end());
#define sz(v) (int)v.size()
//#define int long long
using namespace std;
typedef vector<int> vi;
#define y1 abacaba
#define left sefude
#define db(x) cerr << #x <<" == "<<x << endl;
#define db2(x,y) cerr<<#x <<" == "<<x<<", "<<#y<<" == "<<y<<endl;
#define db3(x,y,z) cerr << #x<<" == "<<x<<", "<<#y<<" == "<<y<<", "<<#z<<" == "<<z<<endl; 
#define prl cerr<<"called: "<< __LINE__ << endl;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
inline ll mod(ll n, ll m ){ ll ret = n%m; if(ret < 0) ret += m; return ret; }
ll gcd(ll a, ll b){return (b == 0LL ? a : gcd(b, a%b));}
ll exp(ll a,ll b,ll m){
    if(b==0LL) return 1LL;
    if(b==1LL) return mod(a,m);
    ll k = mod(exp(a,b/2,m),m);
    if(b&1LL){
        return mod(a*mod(k*k,m),m);
    }
    else return mod(k*k,m);
}

const int N = 1e6 + 10;
char A[N],B[N];

int dp[N][4][4];
int vis[N][4][4];
int n;
// 3->nada
// 2-> flip
// 1-> all 1's
// 0-> all 0's
inline bool good(int id,int c){
  if(c == 3)return A[id] == B[id];
  if(c == 2)return A[id] != B[id];
  if(c==1)return B[id] == '1';
  return B[id] == '0';
}

int solve(int id,int cur,int beh){// cur operation/operation behind this one
  if(id == n + 1)return 0;
  if(vis[id][cur][beh])return dp[id][cur][beh];
  vis[id][cur][beh]=1;
  int &x = dp[id][cur][beh] = 1e9;
  // deixa como ta:
  if(good(id,cur)){
    x = min(x,solve(id+1,cur,beh));
  }
  // close cur:
  if(beh!=3)x = min(x,solve(id,beh,3));
  // close everything:
  if(cur!=3 and beh == 3)x = min(x,solve(id,3,3));

  for(int nv=0;nv<3;nv++){
    if(good(id,nv)){
      // open a new one and mainting beh:
      x = min(x,1 + solve(id+1,nv,beh));
      // open a new one and put cur behind:
      x = min(x,1 + solve(id+1,nv,cur));
      // open a new one with nothing behind:
      x = min(x,1 + solve(id+1,nv,3));
    }
  }


  return x;
}

int32_t main(){
  fastio;
  cin >> n;
  for(int i=1;i<=n;i++)cin >> A[i];
  for(int i=1;i<=n;i++)cin >> B[i];

  cout << solve(1,3,3) << endl;    
  // math -> gcd it all
  // Did u check N=1? Did you switch N,M?
}

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