自己写的一个算法：将一个int型数转换为string

char *itoa(int num, char *str){assert(NULL != str);int i=1, j=0;if (num < 0){str[j++]='-';num = (-1)*num;}if (0 == num){str[j++] = '0';str[j] = '\0';return str; }while (! (num/i < 10)){i = i*10;}while (num > 0){str[j++] = num/i + 0x30;num = num % i;i = i/10;}str[j]='\0';return(str);
}