高精度乘法

一如既往的重载运算符
sto zhx orz

#include<iostream>
#include<cstdlib>
#include<cstring>
using namespace std;

struct gaojing {
    int z[123456];
    int l;

    gaojing() {
        memset(z,0,sizeof(z));
        l=1;
    }

    friend istream& operator>>(istream &cin,gaojing &v) {
        static char s[100000];
        cin >> s;
        int l=strlen(s);
        for (int a=0; a<l; a++)
            v.z[a] = s[l-a-1] - '0';
        v.l=l;

        return cin;
    }

    friend ostream& operator<<(ostream &cout,const gaojing &v) {
        for (int a=v.l-1; a>=0; a--)
            cout << v.z[a];

        return cout;
    }
};

gaojing operator*(const gaojing &a,const gaojing &b) {
    gaojing c;
    int l = a.l+b.l;
    for(int i=0; i<a.l; i++)
        for(int j=0; j<b.l; j++)
            c.z[i+j] += a.z[i] * b.z[j];
    for(int i=0; i<l; i++){
        c.z[i+1] += c.z[i] /10;
        c.z[i] = c.z[i] % 10;
    }
    while(l>0 && c.z[l]==0) l--;
    l++;
    c.l=l;

    return c;
}

int main() {
    gaojing a,b;
    cin >> a >> b;
    cout << a*b << endl;
}