find max palindrome

#include "stdafx.h"

bool is_pal(char * str);
void reverse(char *x, int begin, int end);
void reverse(char *x);

int _tmain(int argc, _TCHAR* argv[]){
    char numc[10];
    sprintf(numc,"%d",123456);
    int a=999,b=999,numi = 0, found = 0;
    while (b > 99){
        for (int i = a; i >= b; --i ){
            numi = b * i;
            sprintf(numc, "%d", numi);
            if (is_pal(numc) == 0){
                if(numi > found){
                    found = numi;
                }
                //printf("found!\n");
            }
        }
        --b;
    }
    printf("palindrome is '%d'\n", found);
    return 0;
}

bool is_pal(char * str){
    size_t len = strlen(str);
    char * rev;
    rev = new char[len+1];
    strcpy(rev, str);
    reverse(rev);
    bool it_is = strcmp(str,rev);
    delete [] rev;
    return it_is;
}

void reverse(char *x){
    reverse(x, 0, strlen(x)-1);
}

void reverse(char *x, int begin, int end){
    char c;
    if (begin >= end)
        return;
    c = *(x+begin);
    *(x+begin) = *(x+end);
    *(x+end) = c;

    reverse(x, ++begin, --end);
}