string c="";
	int aa[2005]={}, bb[2005]={}, cc[2005]={};
	int lena = a.length();
	int lenb = b.length();
	int lenc = max(lena, lenb);
	for(int i=0;i<lena;i++){
		aa[i] = a[lena-1-i]-48;
	}
	for(int i=0;i<lenb;i++){
		bb[i] = b[lenb-1-i]-48;
	}
	int x = 0;
	for(int i=0;i<lenc;i++){
		cc[i] = aa[i] + bb[i] + x;
		x = cc[i]/10;  
		cc[i] %= 10;  
	} 
	if(x == 1) cc[lenc++] = x;
	while(cc[lenc-1]==0&&lenc-1>0) lenc--;
	for(int i=0;i<lenc;i++)c+=char(cc[lenc-i-1]+48);
	return c;
}