大数相加算法

思路就是存数据，怎么大都不再怕啦！

#include "stdio.h"
#include "string.h"

char m1[1001];
char m2[1001];

int BigAdd(int a,int b){
	printf("a:%d,b:%dn",a,b);
	sprintf(m1,"%d",a);
	sprintf(m2,b);
	
	int len1 = strlen(m1);
	int len2 = strlen(m2);
	
	char sum[1003];
	for(int i = 0; i < sizeof(sum)/sizeof(*sum); ++i){
		sum[i] = '0';
	}
	
	--len1;
	--len2;
	int sumIndex = 1002;
	int flag = 0;
	
	while(len1 >= 0 && len2 >= 0){
		int temp = m1[len1]-'0' + m2[len2]-'0'+flag;
		
		flag = temp/10;
		if(flag > 0){
			temp %= 10;
		} 
		
		sum[sumIndex] = temp + '0';
		--len1;
		--len2;
		--sumIndex;
	}
	
	while(len1 >= 0){
		int temp = m1[len1]-'0'+flag;
		
		flag = temp/10;
		if(flag > 0){
			temp %= 10;
		} 
		
		sum[sumIndex] = temp + '0';
		--len1;
		--sumIndex;
	}
	
	while(len2 >= 0){
		int temp = m2[len2]-'0'+flag;
		
		flag = temp/10;
		if(flag > 0){
			temp %= 10;
		}
		
		sum[sumIndex] = temp + '0';
		--len2;
		--sumIndex;
	}
	
	if(flag == 1){
		sum[sumIndex] = flag + '0';
		--sumIndex;
	}
	
	for(int i = sumIndex+1; i < 1003; ++i){
		printf("%c",sum[i]);
	}
	
	printf("n");
}
int main(){
	BigAdd(100001111,999999999);
}