华为OJ 购物结算系统

主要是读题比较复杂

用到了函数指针，运算符重载，结构体

#include<iostream>
#include<cstdio>
#include<list>
#include<string>
#include<cstring>
#define MAX_NUM 0xfffffff
using namespace std;
typedef struct  
{
	int goodID;
	int goodNums;
} Good;

bool operator == (Good good1,Good good2)
{
	return (good1.goodID==good2.goodID&&good1.goodNums==good2.goodNums);
}

typedef int (*GetmoneyFun)(int);
list<Good> g_goods_car;
int g_money=3000;
int g_credit=150;

//第一种商品(食品)的支付方式
int FirstGoodPay1(int goodNums)
{
	return goodNums*10;
}

int FirstGoodPay2(int goodNums)
{
	return goodNums*9;
}

int FirstGoodPay3(int goodNums)
{
	int result=goodNums*10;
	int count=result/100;
	result-=count*18;
	return result;
}
//第一种商品(食品)的支付方式

//第二种商品（服装）的支付方式
int SecondGoodPay1(int goodNums)
{
	return goodNums*120;
}

int SecondGoodPay2(int goodNums)
{
	int result=goodNums*120;
	int count=result/200;
	result-=count*40;
	return result;
}
//第二种商品（服装）的支付方式

//第三种商品（书籍）的支付方式
int ThirdGoodPay1(int goodNums)
{
	return goodNums*30;
}

int ThirdGoodPay2(int goodNums)
{
	return goodNums*15;
}
//第三种商品（书籍）的支付方式

GetmoneyFun payFood[3]={FirstGoodPay1,FirstGoodPay2,FirstGoodPay3};
GetmoneyFun payCloth[2]={SecondGoodPay1,SecondGoodPay2};
GetmoneyFun payBook[2]={ThirdGoodPay1,ThirdGoodPay2};

void GetFinalPay()
{
	int foodNums=0,clothNums=0,bookNums=0;
	list<Good>::iterator it;
	for(it=g_goods_car.begin();it!=g_goods_car.end();it++)
	{
		if((*it).goodID==0)
			foodNums+=(*it).goodNums;
		else if((*it).goodID==1)
			clothNums+=(*it).goodNums;
		else
			bookNums+=(*it).goodNums;
	}
	int result=MAX_NUM;
	bool useCredit=false;
	for(int i=0;i<3;i++)
	{
		for(int j=0;j<2;j++)
		{
			for(int k=0;k<2;k++)
			{
				int now=payFood[i](foodNums)+payCloth[j](clothNums)+payBook[k](bookNums);
				if(now>=500)
				{
					int payFinal_1=now*0.8<=g_money?now*0.8:MAX_NUM;
					int payFinal_2=MAX_NUM;
					int tempPay;
					if(g_credit>=120)
					{
						tempPay=now-120;
					}
					else
					{
						tempPay=now-g_credit;
					}
					payFinal_2=tempPay<=g_money?tempPay:MAX_NUM;
					if(payFinal_1<=payFinal_2)
					{
						now=payFinal_1;
						useCredit=false;
					}
					else
					{
						now=payFinal_2;
						useCredit=true;
					}
				}
				else
				{
					if(now>g_money)
						now=MAX_NUM;
					else
						useCredit=false;
				}
				if(now<result)
				{
					result=now;
				}
			}
		}
	}
	if(result<MAX_NUM)
	{
		printf("%d\n",result);
		if(useCredit)
		{
			if(g_credit>120)
			{
				g_credit-=120;
				printf("120\n");
			}
			else
			{
				printf("%d\n",g_credit);
				g_credit=0;
			}
		}
		else
		{
			printf("0\n");
		}
		int creditAdd=result/10;
		printf("%d\n",creditAdd);
		g_credit+=creditAdd;
		g_money-=result;
		g_goods_car.clear();
	}
	else
	{
		printf("E006\n");
	}
}

void Initial()
{
	g_goods_car.clear();
	g_money=3000;
	g_credit=150;
	printf("S001\n");
}

void PickGoods(int goodID,int goodNums)
{
	if(goodID<0||goodID>2||goodNums<=0||goodNums>100)
	{
		printf("E002\n");
	}
	else if(!g_goods_car.empty()&&g_goods_car.size()>=5)
	{
		printf("E003\n");
	}
	else
	{
		Good newGood;
		newGood.goodID=goodID;
		newGood.goodNums=goodNums;
		g_goods_car.push_back(newGood);
		printf("S002\n");
	}
}

void DeleteGoods(int goodID,int goodNums)
{
	if(goodID<0||goodID>2||goodNums<=0||goodNums>100)
	{
		printf("E002\n");
	}
	else if(g_goods_car.empty())
	{
		printf("E005\n");
	}
	else
	{
		list<Good>::iterator it;
		int count=0;
		Good now;
		now.goodID=goodID;
		now.goodNums=goodNums;
		for(it=g_goods_car.begin();it!=g_goods_car.end();it++)
		{
			if((*it)==now)
			{
				count++;
			}
		}
		if(!count)
		{
			printf("E004\n");
		}
		else
		{
			g_goods_car.remove(now);
			for(int i=0;i<count-1;i++)
				g_goods_car.push_back(now);
			printf("S003\n");
		}
	}
}

void BuyGoods()
{
	if(g_goods_car.empty())
	{
		printf("E005\n");
	}
	else
	{
		GetFinalPay();
	}
}

void Query(int queryType)
{
	if(queryType==0)
	{
		printf("%d\n",g_money);
		printf("%d\n",g_credit);
	}
	else
	{
		int foodNums=0,clothNums=0,bookNums=0;
		list<Good>::iterator it;
		for(it=g_goods_car.begin();it!=g_goods_car.end();it++)
		{
			if((*it).goodID==0)
				foodNums+=(*it).goodNums;
			else if((*it).goodID==1)
				clothNums+=(*it).goodNums;
			else
				bookNums+=(*it).goodNums;
		}
		printf("%d\n",g_goods_car.size());
		printf("%d\n",foodNums);
		printf("%d\n",clothNums);
		printf("%d\n",bookNums);
	}
}

int main()
{
	//freopen("data.txt","r",stdin);
	char inputStr[200];
	while(gets(inputStr)!=NULL)
	{
		int startPos=0;
		int len=strlen(inputStr);
		while(startPos<len&&inputStr[startPos++]==' ');
		startPos--;
		switch (inputStr[startPos])
		{
		case 'r':
			Initial();
			break;
		case 'o':
			{
				int goodID,goodNums;
				sscanf(&inputStr[startPos+2],"%d",&goodID);
				sscanf(&inputStr[startPos+4],"%d",&goodNums);
				PickGoods(goodID,goodNums);
			}
			break;
		case 'c':
			{
				int goodID,goodNums;
				sscanf(&inputStr[startPos+2],"%d",&goodID);
				sscanf(&inputStr[startPos+4],"%d",&goodNums);
				DeleteGoods(goodID,goodNums);
			}
			break;
		case 'b':
			BuyGoods();
			break;
		case 'l':
			{
				int queryType;
				sscanf(&inputStr[startPos+2],"%d",&queryType);
				Query(queryType);
			}
			break;
		case 'e':
			return 0;
		default:
			printf("E001\n");
			break;
		}
	}
	return 0;
}