C语言十进制原码转十六进制的函数接口
时间: 2023-09-24 16:03:16 浏览: 100
嵌入式学习-01C语言day03
以下是将十进制原码转换为十六进制的C语言函数接口:
```c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
char *dec_to_hex(int decimal_num) {
int is_negative = 0;
char *hex_str = (char *)malloc(sizeof(char) * 9);
memset(hex_str, 0, sizeof(char) * 9);
// 判断数字是否为负数
if (decimal_num < 0) {
is_negative = 1;
decimal_num = abs(decimal_num);
}
// 将数字转换为十六进制
int index = 0;
while (decimal_num > 0) {
int remainder = decimal_num % 16;
if (remainder < 10) {
hex_str[index++] = remainder + '0';
} else {
hex_str[index++] = remainder - 10 + 'A';
}
decimal_num /= 16;
}
// 如果是负数,需要将十六进制字符串取反后再加1
if (is_negative) {
for (int i = 0; i < strlen(hex_str); i++) {
if (hex_str[i] >= '0' && hex_str[i] <= '9') {
hex_str[i] = 'F' - (hex_str[i] - '0') + 1;
} else if (hex_str[i] >= 'A' && hex_str[i] <= 'F') {
hex_str[i] = 'F' - (hex_str[i] - 'A') + 1;
}
}
hex_str = add_one(hex_str);
}
// 反转字符串
int len = strlen(hex_str);
for (int i = 0; i < len / 2; i++) {
char tmp = hex_str[i];
hex_str[i] = hex_str[len - i - 1];
hex_str[len - i - 1] = tmp;
}
return hex_str;
}
char *add_one(char *hex_str) {
int carry = 1;
int len = strlen(hex_str);
char *result = (char *)malloc(sizeof(char) * (len + 1));
memset(result, 0, sizeof(char) * (len + 1));
for (int i = len - 1; i >= 0; i--) {
char digit = hex_str[i];
if (digit >= '0' && digit <= '8' && carry == 1) {
result[i] = digit + 1;
carry = 0;
} else if (digit == '9' && carry == 1) {
result[i] = 'A';
carry = 0;
} else if (digit == 'A' && carry == 1) {
result[i] = 'B';
carry = 0;
} else if (digit == 'B' && carry == 1) {
result[i] = 'C';
carry = 0;
} else if (digit == 'C' && carry == 1) {
result[i] = 'D';
carry = 0;
} else if (digit == 'D' && carry == 1) {
result[i] = 'E';
carry = 0;
} else if (digit == 'E' && carry == 1) {
result[i] = 'F';
carry = 0;
} else {
result[i] = digit;
}
}
if (carry == 1) {
result[0] = '1';
}
return result;
}
```
调用方式:
```c
#include <stdio.h>
int main() {
// 将十进制数 -10 转换为十六进制
char *hex_str = dec_to_hex(-10);
printf("%s\n", hex_str); // 输出结果为 FFFFFFF6
free(hex_str);
return 0;
}
```
这个函数可以将任意十进制数字转换为十六进制,包括负数。当输入为负数时,会将其转换为原码后再转换为十六进制。需要注意的是,返回的十六进制字符串需要手动释放。
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