C + + implements large number multiplication

#include <string.h> #include <iostream> #import <foundation/foundation.h>using namespace std;# Define INT (x) (X-' 0 ') #define CHAR (x) (x + ' 0 ') char a[100]={0};char b[100]={0};//quadrature char *multibiginteger (char *, char *) ;//Check whether the digits of each number meet the requirements bool Checknum (char *);//print void num (char*,int) for the desired product,//for length int len (char*), int main () {while (scanf ("%s% S ", A, B)) {if (Checknum (a) | | Checknum (b)) {continue;} else{char * arr = Multibiginteger (A, b); Num (arr, Len (arr));} cout<<a<<endl<<b<<endl; } return 0;} BOOL Checknum (char *ch) {bool Bo = NO; char * temp = ch; int lan = 0; while (Lan<strlen (temp)) {//) as long as there is a range that does not return within 0 to 9 Flase if (temp[lan]< ' 0 ' | | temp[lan]> ' 9 ') {bo = YES; cout<< "<<temp[lan]<<" you entered does not meet the requirements, can only enter 1 to 9 any one!!! "<<endl; Break } ++temp; ++lan; } return Bo; void num (char* a,int len) {int temp = len; cout<< "product is:";//temp-=1; for (; temp>=0;temp--) {if (!) ( (Temp==len) && (a[temp]== ' 0 ')) {cout<<a[temp];} Cout<<a[temp]; } Cout<<endl;} Ask for an array of length int len (char* a) {int len=0; while (*a) {++a; ++len;} return len;} Char *multibiginteger (char *a, char *b) {int lengtha = Len (a),//a length int lengthb = len (b);//b length char* Arrayab = Nullpt R Application for a memory storage product//arrayab= (char*) malloc ((lengthb+lengtha-1) *sizeof (char)); arrayab= New Char[lengthb+lengtha]; memset (Arrayab, ' 0 ', (lengthb+lengtha) *sizeof (char)); cout<<arrayab[0]<<endl; int ji = 0; int Jigewei = 0; int Jijinwei = 0; int he = 0; int Hegeiwei = 0; int Hejinwei = 0; int Painyi = 0; int temp = 0; for (int i = lengthb-1; i>=0; i--) {//b Painyi = temp, for (int j = lengtha-1; j>=0; j--) {//a char ChB = b[i]; char Cha = a[j];//cout<<cha<<chb<<endl;//cout<< a[i]<<b[j]<<endl; Ji = Int (ChB) *int (cha) +jijinwei; Jigewei =ji%10; Jijinwei = ji/10;//cout<< "Lengtha" <<lengtha<< "LENGTHB" <<lengthb<< "Ji" <<ji <<int (CHA) <<int (CHB) <<endl; he = JigeWei+hejinwei+int (Arrayab[painyi]); Hegeiwei= he%10; Hejinwei= HE/10; Arrayab[painyi]=char (Hegeiwei); Arrayab[painyi+1]=char (Jijinwei); ++painyi; } ++temp; } return Arrayab;}

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C + + implements large number multiplication