笔试面试题11--整数与字符串转化

面试例题1：怎样将整数转化成字符串数，并且不用函数itoa？

# if 0//整数转化为字符串，不使用itoa()# include <stdio.h>int main(){    int num = 12345;    int i = 0;    char temp[7],str[7];    while(num)    {        temp[i] = num%10 + '0';//转化为字符        i++;        num = num/10;    }    temp[i] = '\0';//添加字符串末尾标识符    printf("temp = %s\n",temp);    i = i - 1;    printf("temp = %d\n",i);    while(i >= 0)//逆序输出字符串    {        str[j] = temp[i];        j++;        i--;    }    str[j] = '\0';    printf("string = %s\n",str);    return 0;}# endif

面试例题2：编程实现字符串数转化成整数的办法。

# if 1//字符串转化为整数，不使用atoi()# include <stdio.h>int main(){    int num = 12345;    int i = 0;    int sum = 0;    char temp[7] = {'1','2','3','4','5','\0'};    while(temp[i])    {        sum = sum * 10 + (temp[i] - '0');        i++;    }    printf("sum = %d\n",sum);    return 0;}# endif