#include <iostream>
#include <string>
using namespace std;
/* 请在这里填写答案 */
class BigInteger{
protected:
int a[3005];
int count;
public:
BigInteger(){
for(int i=0;i<3005;i++){
a[i]=0;
}
count=0;
}
friend BigInteger operator *(BigInteger &a,BigInteger &b){
BigInteger c;
int k=a.count+b.count;
for(int i=a.count-1;i>=0;i--){
for(int j=b.count-1;j>=0;j--){
c.a[i+j+1]+=a.a[i]*b.a[j];
if(c.a[i+j+1]>9){
c.a[i+j]+=c.a[i+j+1]/10;
c.a[i+j+1]%=10;
}
}
}
c.count=k;
return c;
}
friend istream& operator >> (istream &in,BigInteger &s){
string s1;
in>>s1;
for(int i=0;i<s1.size();i++){
s.a[i]=s1[i]-‘0‘;
s.count++;
}
return in;
}
friend ostream& operator << (ostream &o,BigInteger &s){
int flag=1;
for(int i=0;i<s.count;i++){
if(s.a[i]!=0){
flag=0;
}
if(flag==0){
o<<s.a[i];
}
}
if(flag==1){
o<<"0";
}
return o;
}
};
int main()
{
BigInteger a, b, c;
cin >> a >> b;
c = a * b;
cout << a << "*" << b << "=" << c << endl;
return 0;
}
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