[模板]高精度四则运算

struct Number{
    int a[N],n;bool POrN; 
    void init(){
        memset(a,0,sizeof(a));
        n=1;POrN=true;
    }
    void read(){
        init();--n;
        char c=getchar();
        while(!isdigit(c)){
            if(c=='-') POrN=false;
            c=getchar();
        }
        while(isdigit(c)){
            a[n++]=c-'0';c=getchar();
        }
    }
    void write(){
        if(!POrN) cout<<"-";
        for(int i=0;i (const Number a,const Number b){
        return b= (const Number a,const Number b){
        return b<=a;
    }
    void tran(){
        for(int i=0;i<(n>>1);++i){
            swap(a[i],a[n-i-1]);
        }
    }
    Number add(Number a,Number b){
        Number c;c.init();
        c.n=max(a.n,b.n);
        a.tran();b.tran();
        for(int i=0;i=10){
                c.a[i]-=10;++c.a[i+1];
            }
        }
        while(c.a[c.n]) ++c.n;
        c.tran();
        return c;
    }
    Number sub(Number a,Number b){
        Number c;c.init();
        c.n=max(a.n,b.n);
        a.tran();b.tran();
        for(int i=0;i1&&!c.a[c.n-1]) --c.n;
        c.tran();
        return c;   
    }
    friend Number operator + (Number a,Number b){
        Number c;bool fl=false;
        if(a.POrN^b.POrN){
            if(!a.POrN){
                swap(a,b);fl=true;
            }
            if(a.abs(a)10){
                c.a[i+1]+=c.a[i]/10;c.a[i]%=10;
            }
        while(c.n>1&&!c.a[c.n-1]) --c.n;
        a.tran();b.tran();c.tran();
        return c;
    }
    bool cmp(Number c,int s,int t){
        if(t-s>n) return true;
        if(t-sa[i]; 
        }
        return true;
    }
    void sub(Number b,int s,int t){
        for(int i=t-1,j=b.n-1;j>=0;--i,--j){
            a[i]-=b.a[j];
            if(a[i]<0) a[i]+=10,--a[i-1];
        }
        return;
    }
    friend Number operator / (Number a,Number b){
        Number c,d=a;c.init();
        c.POrN=!(a.POrN^b.POrN);c.n=0;
        for(int s=0,t=b.n;t<=d.n;){
            while(b.cmp(d,s,t)){
                d.sub(b,s,t);++c.a[c.n];
                if(!d.a[s]) ++s;
            }
            ++c.n;++t;
            if(!d.a[s]) ++s;
        }
        int cnt=0;
        while(cnt