#include<bits/stdc++.h>
using namespace std;
int m,d;
int months[13]= {31,31,28,31,30,31,30,31,31,30,31,30,31};
int now = 1,nowm = 1;
int dfs()
{
    int ik,un,ans = 0;
    ik = now / 10;
    un = d / 10;
    if(ik != un)
        ans++;
    ik = now % 10;
    un = d % 10;
    if(ik != un)
        ans++;
    ik = nowm / 10;
    un = m / 10;
    if(ik != un)
        ans++;
    ik = nowm % 10;
    un = m % 10;
    if(ik != un)
        ans++;
    return ans;
}
int main()
{
	scanf("%d-%d",&m,&d);
	int j = INT_MAX;
	for(int i = 1;i <= 366;i++)
	{
	    if(now == months[nowm] + 1)
	    {
	        now = 1;
	        nowm++;
	        j = min(dfs(),j);
	        continue; 
	    }
	    j = min(dfs(),j);
	    now++;
	}
	printf("%d",j);
 	return 0;
}