Submission #127194

#	Time	Username	Problem	Language	Result	Execution time	Memory
127194		dndhk	Lamps (JOI19_lamps)	C++14	100 / 100	230 ms	35928 KiB

lamp

#include <bits/stdc++.h>

#define pb push_back
#define all(v) ((v).begin(), (v).end())
#define sortv(v) sort(all(v))
#define sz(v) ((int)(v).size())
#define uniqv(v) (v).erase(unique(all(v)), (v).end())
#define umax(a, b) (a)=max((a), (b))
#define umin(a, b) (a)=min((a), (b))
#define FOR(i,a,b) for(int i = (a); i <= (b); i++)
#define rep(i,n) FOR(i,1,n)
#define rep0(i,n) FOR(i,0,(int)(n)-1)
#define FI first
#define SE second
#define INF 1000000000
#define INFLL 1000000000000000000LL


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

const int MAX_N = 1000000;

int N;
string A, B;
pii type[MAX_N+1];
int dp[MAX_N+10][2][3];

int main(){
	scanf("%d", &N);
	cin>>A;
	cin>>B;
	for(int i=0; i<N; i++){
		type[i+1] = {(A[i] - '0'), (B[i] - '0')};
	}
	for(int i=0; i<2; i++){
		for(int j=0; j<3; j++){
			dp[0][i][j] = INF;
		}
	}
	dp[0][0][0] = 0;
	for(int n=1; n<=N; n++){
		for(int i=0; i<2; i++){
			for(int j=0; j<3; j++){
				dp[n][i][j] = INF;
				for(int i2=0; i2<2; i2++){
					for(int j2=0; j2<3; j2++){
						int pl = 0;
						if(i==1 && i2==0)	pl++;
						if(j!=j2 && j!=0)	pl++;
						dp[n][i][j] = min(dp[n][i][j], dp[n-1][i2][j2] + pl);
					}
				}
				if(type[n].first==0){
					if(type[n].second==0){
						dp[n][0][2] = dp[n][1][0] = dp[n][1][1] = INF;
					}else{
						dp[n][0][0] = dp[n][0][1] = dp[n][1][2] = INF;
					}
				}else{
					if(type[n].second==0){
						dp[n][0][0] = dp[n][0][2] = dp[n][1][1] = INF;
					}else{
						dp[n][0][1] = dp[n][1][0] = dp[n][1][2] = INF;
					}
				}
			}
		}
	}
	int ans = INF;
	for(int i=0; i<2; i++){
		for(int j=0; j<3; j++){
			ans = min(ans, dp[N][i][j]);
		}
	}
	cout<<ans;
	return 0;
}

Compilation message (stderr)

lamp.cpp: In function 'int main()':
lamp.cpp:32:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &N);
  ~~~~~^~~~~~~~~~

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