Submission #1116224

#	Time	Username	Problem	Language	Result	Execution time	Memory
1116224		firewater	Lamps (JOI19_lamps)	C++14	4 / 100	22 ms	29948 KiB

lamp

#include<bits/stdc++.h>
#define N 1001000
using namespace std;
int n,ans,a[N],b[N],f[N][5];
char s1[N],s2[N];
int main()
{
	scanf("%d%s%s",&n,s1+1,s2+1);
	for(int i=1;i<=n;++i)
		a[i]=s2[i]-'0'+1,b[i]=(s1[i]!=s2[i]);
	memset(f,127/3,sizeof(f));
	f[0][0]=0;
	b[0]=-1;
	for(int i=1;i<=n;++i)
		for(int j=0;j<=2;++j){
			f[i][0]=min(f[i][0],f[i-1][j]+(b[i]&&(b[i]!=b[i-1]||j)));
			if(j)f[i][j]=min(f[i][j],f[i-1][j]+(a[i]!=j&&a[i]!=a[i-1]));
			f[i][a[i]]=min(f[i][a[i]],f[i-1][j]+1);
		}
	ans=f[0][1];
	for(int j=0;j<=2;++j)
		ans=min(ans,f[n][j]);
	printf("%d\n",ans);
	return 0;
}

Compilation message (stderr)

lamp.cpp: In function 'int main()':
lamp.cpp:8:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
    8 |  scanf("%d%s%s",&n,s1+1,s2+1);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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