#include <bits/stdc++.h>
using namespace std;
char s1[10090],s2[10090],s3[10090];
int a[10090],b[10090],c[10090];
int flag = 0;
bool compare(char s1[],char s2[])
{
int u = strlen(s1),v=strlen(s2);
if ( u != v )
{
return u > v;
}
for ( int i = 0 ; i < u ; i++ )
{
if ( s1[i] != s2[i] )
{
return s1[i] > s2[i];
}
}
return true;
}
int main()
{
int la,lb,lc;
cin >> s1;
cin >> s2;
if (!compare(s1,s2))
{
flag = 1;
strcpy(s3,s1);
strcpy(s1,s2);
strcpy(s2,s3);
}
la = strlen(s1);
lb = strlen(s2);
for ( int i = 0 ; i < la ; i++ )
{
a[la-i] = s1[i] - '0';
}
for ( int i = 0 ; i < lb ; i++ )
{
b[lb-i] = s2[i] - '0';
}
lc = max(la,lb);
for ( int i = 1 ; i <= lc ; i++ )
{
if ( a[i] < b[i] )
{
a[i+1]--;
a[i] += 10;
}
c[i] = a[i] - b[i];
}
while ( c[lc] == 0 && lc > 1 )
{
lc--;
}
if ( flag == 1 )
{
cout << "-";
}
for ( int i = lc ; i > 0 ; i-- )
{
cout << c[i];
}
return 0;
}