main.cpp

长整数的加减乘 重载了运算符

#include <iostream>
#include "long_number.h"
#include <fstream>
#include <ctime>
#include <conio.h>

using namespace std;

int main(int argc, char *argv[])
{
	
	char op,ch,name[30];
	ifstream infile,f1,f2;
	ofstream out;
	clock_t sta,end;
	long_number a,b,c;
	if(argc==2)
	{
		infile.open(argv[1]);
		infile>>a;
		infile>>op;
		infile>>b;
		cout<<a<<op<<b<<'=';
		switch (op)
		{
		case '+' :
			cout<<a+b<<endl;
			break;
		case '-' :
			cout<<a-b<<endl;
			break;
		case '*' :
			cout<<a*b<<endl;
			break;
		}
		system("pause");
	}
	else
	{
		while(1)
		{
			system("cls");
			cout<<"************大数运算器******************"<<endl;
			cout<<"**1.输入数据"<<endl;
			cout<<"**2.从文件读入数据"<<endl;
			cout<<"**ESC.退出"<<endl;
			ch=getch();
			switch(ch)
			{
			case '1' :
				while(1)
				{
					system("cls");
					cout<<"请输入数字1：";
					cin>>a;
					cout<<"请输入数字2：";
					cin>>b;
					cout<<"请输入运算符：";
					cin>>op;
					cout<<a<<op<<b<<'=';
					switch (op)
					{
					case '+' :
						cout<<a+b<<endl;
						break;
					case '-' :
						cout<<a-b<<endl;
						break;
					case '*' :
						cout<<a*b<<endl;
						break;
					default :
						cout<<"运算符输入有误!!"<<endl;
					}
					cout<<"是否继续?(y/n)";
					ch=getch();
					if(ch!='y'&&ch!='Y')
						break;
				}
				break;
			case '2' :
				while(1)
				{
					system("cls");
					cout<<"请输入文件名1：";
					cin>>name;
					f1.open(name);
					if(!f1)
						cout<<"文件不存在或为空"<<endl;
					f1>>a;
					f1.close();
					cout<<"请输入文件名2：";
					cin>>name;
					f2.open(name);
					if(!f2)
						cout<<"文件不存在或为空"<<endl;
					f2>>b;
					f2.close();
					cout<<"请输入运算符：";
					cin>>op;
					cout<<"情输入输出文件名："<<endl;
					cin>>name;
					out.open(name);
					sta=clock();
					switch (op)
					{
					case '+' :
						out<<a+b<<endl;
						break;
					case '-' :
						out<<a-b<<endl;
						break;
					case '*' :
						out<<a*b<<endl;
						break;
					default :
						cout<<"运算符输入有误!!"<<endl;
					}
					end=clock();
					cout<<"运算耗时"<<end-sta<<"毫秒"<<endl;
					out.close();
					cout<<"是否继续?(y/n)";
					ch=getch();
					if(ch!='y'&&ch!='Y')
						break;
				}
				break;
			case 27 :
				exit(0);
			}
		}

				
	}
	return 1;
}