include[HTML_REMOVED]
include[HTML_REMOVED]
include[HTML_REMOVED]
using namespace std;
string s1, s2;
int i;
vector[HTML_REMOVED]a, b, c;
bool test(vector[HTML_REMOVED]&a, vector[HTML_REMOVED]&b)
{
int i,l1,l2;
l1 = a.size();
l2 = b.size();
if (l1 > l2) return true;
else if (l1 < l2)return false;
else for (i = l1-1; i > 0; i–) if (a[i] > b[i])return true;
else if (a[i] < b[i])return false;
return (a[0] >= b[0]);
}//判断2个数大小
vector[HTML_REMOVED] sub(vector[HTML_REMOVED]&a, vector[HTML_REMOVED]&b)
{
vector[HTML_REMOVED]c;
int t = 0,i;
for (i = 0; i < a.size() || i < b.size();i++)
{
if (i < a.size())t += a[i];
if (i < b.size())t -= b[i];
if (t < 0){ t += 10; a[i + 1]–; }
c.push_back(t);
t=0;//这里填写t/=10会报错,不知道为什么
}
while ((c[–i] == 0)&&(i>0)){ c.erase(c.begin() + i); }
return c;
}
int main() {
std::ios::sync_with_stdio(false);
std::cin.tie(0);
cin >>s1>>s2;
int i;
for ( i = s1.size() - 1; i >= 0; i–)a.push_back(s1[i]-‘0’);
for ( i = s2.size() - 1; i >= 0; i–)b.push_back(s2[i]-‘0’);
if (test(a, b)) c = sub(a, b); else { cout << ‘-‘; c = sub(b, a); }
for (i = c.size() - 1; i >= 0; i–)cout << c[i];
return 0;
}