重载运算符版高精运算

都是自己手写的，重载运算符用起来也比较方便

#include <cstdio>
#include <algorithm>
#include <iostream>
#include <cstring>
using namespace std;
int read(){
	int x = 1,a = 0;char ch = getchar();
	while (ch < '0'||ch > '9'){if (ch == '-') x = -1;ch = getchar();}
	while (ch >= '0'&&ch <= '9'){a = a*10+ch-'0';ch = getchar();}
	return x*a;
}
struct INT{
	int len,a[10007];
	void clear(){len = 1,memset(a,0,sizeof(a));}
	void print(){
		for (int i = len;i >= 1;i--) putchar(a[i]+'0');
		puts("");
	}
	void read(){
		char ch = getchar();clear();len = 0;
		while (ch < '0'||ch > '9') ch = getchar();
		while (ch >= '0'&&ch <= '9'){a[++len] = ch-'0';ch = getchar();}
		for (int i = 1;i < len-i+1;i++) swap(a[i],a[len-i+1]);
	}
	void calc(){
		for (int i = 1;i <= len;i++){
			if (a[i] >= 10) a[i+1] += a[i]/10,a[i] %= 10,len = max(len,i+1);
		}
	}
	void operator = (int b){
		clear();len = 0;
		while (b) a[++len] = b%10,b /= 10;
		len = max(1,len);
	}
	friend INT operator + (const INT a,const INT b){
		INT res;res.clear();res.len = max(a.len,b.len);
		for (int i = 1;i <= res.len;i++) res.a[i] = a.a[i] + b.a[i];
		res.calc();return res;
	}
	friend INT operator + (const INT a,const int b){
		INT c;c = b;return a+c;
	}
	friend INT operator - (const INT a,const INT b){
		INT res;res.clear();res.len = max(a.len,b.len);
		for (int i = 1;i <= res.len;i++) res.a[i] = a.a[i] - b.a[i];
		for (int i = 1;i <= res.len;i++){
			if (res.a[i] < 0) res.a[i] += 10,res.a[i+1] --;
		}
		while (!res.a[res.len]&&res.len > 1) res.len--;
		return res;
	}
	friend INT operator - (const INT a,const int b){
		INT c;c = b;return a-c;
	}
	friend INT operator * (const INT a,const INT b){
		INT res;res.clear();res.len = a.len+b.len-1;
		for (int i = 1;i <= a.len;i++){
			for (int j = 1;j <= b.len;j++) res.a[i+j-1] += a.a[i] * b.a[j];
		}
		res.calc();return res;
	}
	friend INT operator * (const INT a,const int b){
		INT c;c = b;return a*c;
	}
	friend INT operator / (const INT a,const int b){
		INT res;res.clear();res.len = a.len;int tmp = 0;
		for (int i = 1;i <= res.len;i++){
			tmp = tmp*10+a.a[i];
			res.a[i] = tmp/b,tmp %= b;
		}
		while (!res.a[res.len]&&res.len > 1) res.len--;
		return res;
	}
	friend int operator % (const INT a,const int b){
		int tmp = 0;
		for (int i = 1;i <= a.len;i++){
			tmp = tmp*10+a.a[i];
			tmp %= b;
		}
		return tmp;
	}
};
int main(){
	INT a,b;int c = read();
	a.read(),b.read();
	INT ans,ans1,ans2,ans3;
	ans = a+b,ans1 = a-b;
	ans2 = a/c,ans3 = a%c;
	ans.print(),ans1.print(),ans2.print(),ans3.print();
	return 0;
}