oj.uz

Submission #251946

# Submission time Handle Problem Language Result Execution time Memory
251946 2020-07-23T08:20:46 Z nnnnnnnnnnnnnnnn Lamps (JOI19_lamps) C++14
4 / 100
 154 ms 18160 KB 
#include<bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef vector<int> vi;
typedef pair<int,int> ii;
typedef pair<ll,int> pli;
typedef pair<int,ll> pil;
typedef pair<ll,ll> pll;
const int N = 1e6,inf = 1e9;
int n;
string a,b;
int dp[4][N];	
// ->0
// ->1
// flip
int solve()
{
	int i,j,k;
	for(i=0;i<4;i++)
	{
		for(j=0;j<n;j++)
		{
			dp[i][j] = inf;
		}
	}
	if(a[0]==b[0])
	{
		if(a[0]=='0')	dp[0][0] = 1;
		else			dp[1][0] = 1;
		dp[3][0] = 0;
	}
	else
	{
		dp[2][0] = 1;
		if(b[0]=='0')	dp[0][0] = 1;
		else			dp[1][0] = 1;
	}
	for(i=1;i<n;i++)
	{
		for(j=0;j<4;j++)
		{
			for(k=0;k<4;k++)
			{
				dp[j][i] = min(dp[j][i],dp[k][i-1]+1);
			}
		}	
		if(a[i]==b[i])
		{
			dp[2][i] = inf;
			for(j=0;j<4;j++)
			{
				dp[3][i] = min(dp[3][i],dp[j][i-1]);
			}
			if(a[i]=='0')
			{
				dp[0][i] = min(dp[0][i],dp[0][i-1]);
				dp[1][i] = inf;
			}
			else
			{
				dp[1][i] = min(dp[1][i],dp[1][i-1]);
				dp[0][i] = inf;
			}
		}
		else
		{
			dp[3][i] = inf;
			if(a[i]=='0')
			{
				dp[0][i] = inf;
				dp[2][i] = min(dp[2][i],dp[2][i-1]);
				dp[1][i] = min(dp[1][i],dp[1][i-1]);
			}
			else
			{
				dp[1][i] = inf;
				dp[2][i] = min(dp[2][i],dp[2][i-1]);
				dp[0][i] = min(dp[0][i],dp[0][i-1]);
			}
		}
	}
/*	for(i=0;i<4;i++)
	{
		for(j=0;j<n;j++)
		{
			if(dp[i][j]==inf)	printf("! ");
			else
			printf("%d ",dp[i][j]);
		}
		printf("\n");
	}		*/
	int ans = min(min(dp[0][n-1],dp[1][n-1]),min(dp[2][n-1],dp[3][n-1]));
	return ans;
}
int main()
{
	scanf("%d",&n);
	cin >> a >> b;
	int res = solve();
	for(int i=0;i<n;i++)
	{
		if(b[i]=='0')	b[i]='1';
		else			b[i]='0';
	}
	res = min(res,solve()+1);
	printf("%d",res);
}

Compilation message

lamp.cpp: In function 'int main()':
lamp.cpp:97:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ~~~~~^~~~~~~~~

Subtask #1
0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 1 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Incorrect 0 ms 384 KB Output isn't correct
14 Halted 0 ms 0 KB -

Subtask #2
0 / 41.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 1 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Incorrect 0 ms 384 KB Output isn't correct
14 Halted 0 ms 0 KB -

Subtask #3
4.0 / 4.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 0 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 0 ms 384 KB Output is correct
6 Correct 0 ms 384 KB Output is correct
7 Correct 151 ms 18148 KB Output is correct
8 Correct 149 ms 18024 KB Output is correct
9 Correct 153 ms 18160 KB Output is correct
10 Correct 153 ms 18024 KB Output is correct
11 Correct 152 ms 18148 KB Output is correct
12 Correct 150 ms 18024 KB Output is correct
13 Correct 154 ms 18128 KB Output is correct
14 Correct 151 ms 18024 KB Output is correct

Subtask #4
0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 1 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Incorrect 0 ms 384 KB Output isn't correct
14 Halted 0 ms 0 KB -