自动取模类

#include <bits/stdc++.h>
using namespace std;

#define RG register int
#define LL long long

namespace Mod{
    class Modulus{
    public:
        static const LL mo=1000000007LL;
        LL num;
        static LL mod(LL x);
        static void read(Modulus &a);
        static LL expow(LL a,LL m);
        Modulus(const LL x=0LL):num(mod(x)){}
        Modulus(const Modulus &a):num(a.num){}
        void output(){printf("%lld",num);}
        void operator=(const LL x){num=mod(x);}
        void operator=(const Modulus &x){num=x.num;}
        Modulus operator+(const Modulus &rhs){return Modulus(mod(num+rhs.num));}
        Modulus operator-(const Modulus &rhs){return Modulus(mod(num-rhs.num));}
        Modulus operator*(const Modulus &rhs){return Modulus(mod(num*rhs.num));}
        Modulus operator/(const Modulus &rhs){return Modulus(mod(num*expow(rhs.num,mo-2)));}
        Modulus operator+(LL x){return Modulus(mod(num+x));}
        Modulus operator-(LL x){return Modulus(mod(num-x));}
        Modulus operator*(LL x){return Modulus(mod(num*x));}
        Modulus operator/(LL x){return Modulus(mod(num*expow(x,mo-2)));}
        Modulus operator^(LL x){return Modulus(expow(num,x));}
        friend ostream &operator<<(ostream &output,const Modulus &x){
            output<<x.num;return output;
        }
        friend istream &operator>>(istream &input,Modulus &x){
            input>>x.num;
            return input;
        }
    };

    LL Modulus::mod(LL x){
        if(x<0) return (x%mo+mo)%mo;
        else if(x>=mo) return x%mo;
        return x;
    }

    void Modulus::read(Modulus &a){
        LL X=0,w=0; char ch=0;
        while(!isdigit(ch)) {w|=ch=='-';ch=getchar();}
        while(isdigit(ch)) X=(X<<3)+(X<<1)+(ch^48),ch=getchar();
        a.num=mod(w?-X:X);
    }

    LL Modulus::expow(LL a,LL n){
        LL x=1,p=mod(a);
        while(n){
            if(n&1) x=mod(x*p);
            p=mod(p*p);
            n>>=1;
        }
        return x;
    }
};

int main(){
    Mod::Modulus a,b,c;
    Mod::Modulus::read(a);
    Mod::Modulus::read(b);
    Mod::Modulus::read(c);
    cout<<a*b/c<<endl;

    return 0;
}