Submission #107137

#	Time	Username	Problem	Language	Result	Execution time	Memory
107137		hamzqq9	Lamps (JOI19_lamps)	C++14	100 / 100	142 ms	43520 KiB

lamp

#include<bits/stdc++.h>
#define st first
#define nd second
#define pb push_back
#define pf push_front
#define ppb pop_back
#define ppf pop_front
#define umax(x,y) x=max(x,y)
#define umin(x,y) x=min(x,y)
#define ll long long 
#define ii pair<int,int>
#define iii pair<ii,int>
#define iiii pair<ii,ii>
#define sz(x) ((int) x.size())
#define orta ((bas+son)/2)
#define all(x) x.begin(),x.end()
#define pw(x) (1<<(x))
#define inf 1000000009
#define MOD 1000000007
#define N 1000005
#define M 100000
#define LOG 20
#define KOK 300
#define EPS 0.0000001
using namespace std;

int n;
int dp[N][5][2];
char a[N],b[N];

void tr(int ind,int sit,int fp) {

	for(int fl=0;fl<2;fl++) {

		int fc=(fp && !fl);

		if(sit<4) {

			umin(dp[ind][sit][fp],dp[ind-1][sit][fl]+fc);
			umin(dp[ind][sit][fp],dp[ind-1][3-sit][fl]+fc+(sit&1));

			if(!(sit&1)) umin(dp[ind][sit][fp],dp[ind-1][4][fl]+fc+1);

		}
		else {

			for(int j=0;j<5;j++) umin(dp[ind][sit][fp],dp[ind-1][j][fl]+fc);

		}

	}

}

int main() {

	scanf("%d",&n);

	scanf("%s %s",a+1,b+1);

	for(int i=0;i<=n;i++) {

		for(int j=0;j<5;j++) {

			for(int k=0;k<2;k++) {

				dp[i][j][k]=inf;

			}

		}

	}

	dp[0][4][0]=0;

	for(int i=1;i<=n;i++) {

		for(int j=0;j<2;j++) tr(i,j,b[i]-'0');

		for(int j=2;j<4;j++) tr(i,j,1-b[i]+'0');

		tr(i,4,a[i]!=b[i]);

	}

	int ans=inf;

	for(int i=0;i<5;i++) for(int j=0;j<2;j++) umin(ans,dp[n][i][j]);

	printf("%d",ans);

}

Compilation message (stderr)

lamp.cpp: In function 'int main()':
lamp.cpp:57:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ~~~~~^~~~~~~~~
lamp.cpp:59:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%s %s",a+1,b+1);
  ~~~~~^~~~~~~~~~~~~~~~~

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