BigInteger operator - (const BigInteger& b) const {
BigInteger c;
c.s.resize(s.size());
for(int i = 0, g = 0; i < s.size(); i++) {
c.s[i] = s[i] - g;
g = 0;
int sub = (i < b.s.size() ? b.s[i] : 0);
if(c.s[i] < sub) { g = 1; c.s[i] += BASE; }
c.s[i] -= sub;
}
c.adjust();
return c;
}
BigInteger operator * (const BigInteger& b) const {
BigInteger c;
c.s.resize(s.size() + b.s.size() + 1);
fill(c.s.begin(), c.s.end(), 0);
for(int i = 0; i < s.size(); i++)
for(int j = 0; j < b.s.size(); j++) {
long long sum = (long long)s[i] * b.s[j] + c.s[i+j];
c.s[i+j+1] += sum / BASE;
c.s[i+j] = sum % BASE;
}
c.adjust();
return c;
}
BigInteger divmod (int b, int& d) const {
BigInteger c;
c.s.clear();
d = 0;
for(int i = s.size()-1; i >= 0; i--) {
long long v = (long long)d * BASE + s[i];
c.s.push_back(v / b);
d = v % b;
}
reverse(c.s.begin(), c.s.end());
c.adjust();
return c;
}
