无需访问库即可将整数转换为字符串

Question

我最近读了一个求职面试问题示例:

Write a function to convert an integer to a string. Assume you do not have access to library functions i.e., itoa(), etc...

你会怎么做？

Answer 1

快速尝试一下:(经过编辑以处理负数)

int n = INT_MIN;
char buffer[50];
int i = 0;

bool isNeg = n<0;

unsigned int n1 = isNeg ? -n : n;

while(n1!=0)
{
    buffer[i++] = n1%10+'0';
    n1=n1/10;
}

if(isNeg)
    buffer[i++] = '-';

buffer[i] = '\0';

for(int t = 0; t < i/2; t++)
{
    buffer[t] ^= buffer[i-t-1];
    buffer[i-t-1] ^= buffer[t];
    buffer[t] ^= buffer[i-t-1];
}

if(n == 0)
{
    buffer[0] = '0';
    buffer[1] = '\0';
}   

printf(buffer);