#include <bits/stdc++.h>
using namespace std;
typedef signed long long ll;

#undef _P
#define _P(...) (void)printf(__VA_ARGS__)
#define FOR(x,to) for(x=0;x<(to);x++)
#define FORR(x,arr) for(auto& x:arr)
#define FORR2(x,y,arr) for(auto& [x,y]:arr)
#define ITR(x,c) for(__typeof(c.begin()) x=c.begin();x!=c.end();x++)
#define ALL(a) (a.begin()),(a.end())
#define ZERO(a) memset(a,0,sizeof(a))
#define MINUS(a) memset(a,0xff,sizeof(a))
//-------------------------------------------------------

int A,B;

void solve() {
	int i,j,k,l,r,x,y; string s;
	
	cin>>A>>B;
	A=A*3600+B*60;
	
	double X=A%3600/3600.0;
	double Y=A%(12*3600)/(12*3600.0);
	if(abs(X-Y)<1e-9) return _P("0\n");
	
	Y-=X;
	if(Y<0) Y+=1;
	X=1/3600.0-1/(12*3600.0);
	FOR(i,24*60*60) {
		if(Y<=1e-4) {
			cout<<i<<endl;
			return;
		}
		Y-=X;
	}
}


int main(int argc,char** argv){
	string s;int i;
	if(argc==1) ios::sync_with_stdio(false), cin.tie(0);
	FOR(i,argc-1) s+=argv[i+1],s+='\n'; FOR(i,s.size()) ungetc(s[s.size()-1-i],stdin);
	cout.tie(0); solve(); return 0;
}