【51Nod】1005 大数加法

#include<stdio.h>
#include<string.h>
#include<stdlib.h>

void Add (char *tempbuf1,   char *tempbuf2, char *result);  // 大数相加 result = tempbuf1 + tempbuf2

void Sub(char *tempbuf1, char *tempbuf2, char *result);     // 大数相减 result = tempbuf1 - tempbuf2 (默认前者大) 

void Trans (char *str_num1,   char *str_num2, char *tempbuf1, char *tempbuf2); // 大数转化为等长，且最前面添加 “0”

int Compare(char *tempbuf1,char *tempbuf2);//比较两个字符串的长度 相同返回0 buf1长返回1 buf2长返回-1

void  ThrowAway_0 (char *tempbuf );  // 去除结果前面的 连续的无意义的 "0"

int main()
{

	char str1[100001];
	char str2[100001]; 
	char result[100001]={0};
	short result_flag = 0;

	scanf("%s %s",str1,str2);
	
	if(str1[0] == ‘-‘ && str2[0] == ‘-‘)
	{
		str2[0] = str1[0] = ‘0‘;
		Add(str1,str2,result);
		if(result[0]!= ‘0‘)
		{
			printf("-");
			printf("%s\n",result);
		}
		
		else
		printf("0\n");
	}
	else if(str1[0]  == ‘-‘ && str2[0] != ‘-‘)
	{
		str1[0] =‘0‘;

		Sub(str2,str1,result);
		printf("%s\n",result);
	}
	else if(str1[0] != ‘-‘ && str2[0] == ‘-‘)
	{
		str2[0] = ‘0‘;
		Sub(str1,str2,result);
		printf("%s\n",result);
	}
	else
	{
		Add(str1,str2,result);
		printf("%s\n",result);
	}

	return 0;
}


void Trans(char *str_num1, char *str_num2, char *tempbuf1, char *tempbuf2)
{
	int len_num1=0;
	int len_num2=0;
	int i=0;
	while(str_num1[i]!=‘\0‘)
	{
		len_num1++;
		i++;
	}	
	i=0;
	while(str_num2[i]!=‘\0‘)
	{
		len_num2++;
		i++;
	}	

	tempbuf1[0]=‘0‘;
	tempbuf2[0]=‘0‘;

//=======================================================================
	if(len_num2>=len_num1)                                   //补成相同长度
	{
		for(i=1;i<=(len_num2-len_num1);i++)
		{
			tempbuf1[i]=‘0‘;
		}
		for(i=len_num2-len_num1+1;i<=len_num2;i++)
		{
			tempbuf1[i]=str_num1[i-(len_num2-len_num1+1)];
		}
		for(i=1;i<=len_num2;i++)
		{
			tempbuf2[i]=str_num2[i-1];
		}
	}
//------------------------------------------
	else if(len_num2<len_num1)
	{
		for(i=1;i<=(len_num1-len_num2);i++)
		{
			tempbuf2[i]=‘0‘;
		}
		for(i=len_num1-len_num2+1;i<=len_num1;i++)
		{
			tempbuf2[i]=str_num2[i-(len_num1-len_num2+1)];
		}
		for(i=1;i<=len_num1;i++)
		{
			tempbuf1[i]=str_num1[i-1];
		}
	}

}

	
void Add(char *tempbuf1,   char *tempbuf2, char *result) // 大数相加 result = tempbuf1 + tempbuf2
{
	char buf1[100001]={0};
	char buf2[100001]={0};
	Trans(tempbuf1,tempbuf2,buf1,buf2);
	strcpy(tempbuf1,buf1);
	strcpy(tempbuf2,buf2);

	int i=0;
	int temp=0;
	int jinwei=0;
	int len=0;
	while(tempbuf1[i]!=‘\0‘)
	{
		len++;
		i++;
	}
	for(i=len-1;i>=0;i--)
	{   
		temp=(int)(tempbuf1[i]+tempbuf2[i]+jinwei-96);
		if(temp>=10)
		{
			temp=temp-10;
			jinwei=1;
		}
		else jinwei=0;
		result[i]=(char)(temp+48);	
	}
	ThrowAway_0 (result);

}

//================================================

void  ThrowAway_0 (char *tempbuf )  // 去除结果前面的 连续的无意义的 "0"
{
	char buf[100000]={0};

	int n = strlen(tempbuf)-1;
	int i=0;
	while(i<n)
	{
		if (tempbuf[i]!=‘0‘)
		{
			break;
		}
		else 
		{
			i++;
		}
	}
	int Throw = i;
	for (i=0;i<=n-Throw;i++)
	{
		buf[i]=tempbuf[i+Throw];
	}

	strcpy(tempbuf,buf);

}

//=======================================================

//extern "C" __declspec(dllexport) 
void Sub(char *tempbuf1, char *tempbuf2, char *result)     // 大数相减 result = tempbuf1 - tempbuf2
{
	ThrowAway_0 (tempbuf1);
	ThrowAway_0 (tempbuf2);
	memset(result,0,200);
	char buf1[100001]={0};
	char buf2[100001]={0};
	Trans(tempbuf1,tempbuf2,buf1,buf2);
	memset(tempbuf1,0,100001);
	memset(tempbuf2,0,100001);

	strcpy(tempbuf1,buf1);
	strcpy(tempbuf2,buf2);

	int i=0;
	int temp=0;
	int jiewei=0;
	int len=0;
	int ret=1;

	while(tempbuf1[i]!=‘\0‘)    // tempbuf1 和 tempbuf2 的长度相等
	{
		len++;
		i++;
	}
	
	ret = Compare(tempbuf1,tempbuf2);
	if(ret==1)
	{
		for(i=len-1;i>=0;i--)
		{  
			temp = (int)tempbuf1[i] - (int)tempbuf2[i] - jiewei;
			if (temp>=0)
			{
				result[i]=(char)(temp+48);
				jiewei=0;
			}
			else if (temp<0)
			{
				result[i]=(char)(temp+10+48);
				jiewei=1;
			}
		}
		ThrowAway_0 (result);
	}
	else if(ret==0) 
	{
		memset(result,0,100001);
		result[0]=‘0‘;
	}
	else if(ret==-1) 
	{
		for(i=len-1;i>=0;i--)
		{  
			temp = (int)tempbuf2[i] - (int)tempbuf1[i] - jiewei;
			if (temp>=0)
			{
				result[i]=(char)(temp+48);
				jiewei=0;
			}
			else if (temp<0)
			{
				result[i]=(char)(temp+10+48);
				jiewei=1;
			}
		}
		ThrowAway_0 (result);
		memset(buf1,0,100001);
		sprintf(buf1,"-%s",result);	
		strcpy(result,buf1);
	}
	
}

//======================================================================

//===================================================================================

int Compare(char *tempbuf1,char *tempbuf2)
{
	ThrowAway_0 (tempbuf1);
	ThrowAway_0 (tempbuf2);
	char buf1[100001]={0};
	char buf2[100001]={0};
	Trans(tempbuf1,tempbuf2,buf1,buf2);
	memset(tempbuf1,0,100001);
	memset(tempbuf2,0,100001);
	strcpy(tempbuf1,buf1);
	strcpy(tempbuf2,buf2);
	

	int ret=1;
	int count=0;	
	while(count<100001)
	{
		
		int m=(int)tempbuf1[count]-48;
		int n=(int)tempbuf2[count]-48;
		if(m==n)
		{
			count++;
			ret=0;
		}
		else if(m>n)
		{
		//	printf("tempbuf1>tempbuf2\n");
			ret=1;
			break;
			
		}
		else if(m<n)
		{
		//	printf("tempbuf1<tempbuf2\n");
			ret=-1;
			break;
		}
	}
	return ret;
}