strToIntとintToStrの自己定義

#include 
#include 
#include 
using namespace std;

char  *intToStr(int &Number)
{
    char *str = (char *)malloc(12*sizeof(char));
    memset(str, 0, 12*sizeof(char));
    
    char ch, *left, *right;
    left = right = str;
    //    
    unsigned int value = 0;
    if (Number<0) {
        value = -Number;
        *str = '-';
        left++;right++;
    }else{
        value = (unsigned int)Number;
    }
    //      
    while (value) {
        *right = value % 10 +'0';
        value = value/10;
        right++;
    }
    *right = '\0';
    //  
    right--;
    while (right>left) {//            
        ch = *left;
        *left++ = *right;
        *right-- = ch;
    }
    return str;
}

int strToInt(char*& str)
{
    int i =0;
    int num = 0;
    long len = strlen(str);
    if (*str == '-')
    {
        i++;
    }
    while(i

検証＃ケンショウ＃

int main(int argc, char* argv[])
{
    int i = -1234;
    char* s = intToStr(i);
    puts(s);
    free(s);
    s = (char *)"-4321";
    int num = strToInt(s);
    printf("%d
",num);
}