yuan解

#include<bits/stdc++.h>
using namespace std;
int main(){
string a,b,tmp;
cin>>a>>b;
if(b.size()>a.size() || (a.size()==b.size() && b>a)){
tmp=a;
a=b;
b=tmp;
cout<<'-';
}
int az=a.size();
int bz=b.size();
int abz=max(az,bz);
int ar[abz];
ar[abz-1]=0;
for(int i=0;i<abz;i++)
{
int aa=0,bb=0;
if(i<az)
aa=a[az-i-1] - '0';
if(i<bz)
bb=b[bz-i-1] - '0';
ar[i]=aa-bb;
}
for(int i=0;i<abz;i++)
{
if(ar[i]>=10)
{
ar[i+1]+=ar[i]/10;
ar[i]+=10;
}
}
bool ok = false;
for(int i=abz-1; i>=0; i--)
{
if(not ok && ar[i] != 0)
ok = true;
if(ok)
cout << ar[i];
}

return 0;	

}