include <bits/stdc++.h>

using namespace std; string a, b, d; long long a1[20000], b1[20000], c[20000], k[20000], s = 0, n = 0, m = 0;

void reverse(string d, long long k[]) {

long long n = d.size(), j = 0;
for (int i = n - 1; i >= 0; i--) {
	k[j] = d[i] - '0';
	j++;
}

}

int main() {

getline(cin, a);
getline(cin, b);
reverse(a, a1);
reverse(b, b1);
m = a.size();
n = b.size();
if ((m > n) || (n == m && a[0] < b[0])) {
	cout << '-';
	reverse(b, a1);
	reverse(a, b1);
} else {
	reverse(a, a1);
	reverse(b, b1);
}
for (int i = 0; i < 20000; i++) {
	c[i] += a1[i] - b1[i];
	if (c[i] < 0) {
		c[i] += 10;
		c[i + 1] -= 1;
	}
}
for (int i = 20000 - 1; i >= 0; i--) {
	if (c[i] != 0) {
		s = i;
		break;
	}
}
for (int i = s; i >= 0; i--) {
	cout << c[i];
}
return 0;

}