这句话*ptr++ = "zyxwvutsrqponmlkjihgfedcba9876543210123456789abcdefghijklmnopqrstuvwxyz"[35 +(tmp_value - value * base)];很有意思
[C] 纯文本查看 复制代码 /**
* C++ version 0.4 char* style "itoa":
* Written by Lukás Chmela
* Released under GPLv3.
*/
char *itoa(int value, char *result, int base) {
// check that the base if valid
if (base < 2 || base > 36) {
*result = '\0';
return result;
}
char *ptr = result, *ptr1 = result, tmp_char;
int tmp_value;
do {
tmp_value = value;
value /= base;
*ptr++ = "zyxwvutsrqponmlkjihgfedcba9876543210123456789abcdefghijklmnopqrstuvwxyz"[35 +
(tmp_value - value * base)];
} while (value);
// Apply negative sign
if (tmp_value < 0) *ptr++ = '-';
*ptr-- = '\0';
while (ptr1 < ptr) {
tmp_char = *ptr;
*ptr-- = *ptr1;
*ptr1++ = tmp_char;
}
return result;
} |