大数专题A - A + B Problem II

#include <stdio.h>
#include <string.h>
main()
{
	char a[1010],b[1010];int T,k,aa[1010],bb[1010],cc[1010],lena,lenb,lenc,i,x,flag=0;
	freopen("1.txt","r",stdin);
	//freopen("2.txt","w",stdout);
	scanf("%d",&T);
	for(k=1;k<=T;k++)
	{
		memset(a,'',sizeof(a));memset(b,'',sizeof(b));
		scanf("%s%s",&a,&b);lena=strlen(a);lenb=strlen(b);
		memset(aa,0,sizeof(aa));memset(bb,0,sizeof(bb));memset(cc,0,sizeof(cc));
		for(i=0;i<lena;i++)aa[lena-i-1]=a[i]-48;//把lena-i-1改成lena-i就会报错
		for(i=0;i<lenb;i++)bb[lenb-i-1]=b[i]-48;
		lenc=0;x=0;
		while(lenc<lena||lenc<lenb)
		{
			cc[lenc]=aa[lenc]+bb[lenc]+x;
			x=cc[lenc]/10;
			cc[lenc]%=10;
			lenc++;
		}
		cc[lenc]=x;
		if(cc[lenc]==0)lenc--;
		if(flag)printf("nCase %d:n",k);
		if(!flag){flag=1;printf("Case %d:n",k);}
		printf("%s + %s = ",a,b);
		for(i=lenc;i>=0;i--)printf("%d",cc[i]);
		putchar('n');
	}
	return 0;
}

2
1 2
112233445566778899 998877665544332211

Case 1:
1 + 2 = 3

Case 2:
112233445566778899 + 998877665544332211 = 1111111111111111110