char string[100] = "000000000000000000010000000000" this is the data i have and the data is in bits that 4 individual 8 bits that is when we split string[100] we get, 00000000 00000000 00000100 00000000 can anyone help me convert it to hex value using C language?
for the above string ,after converting it to hex we need to get " 00 00 04 00 " so similarly based on the input i need to get a desired output.
CodePudding user response：
No need to re-invent the wheel, just use strtol.
#include <stdio.h>
#include <stdlib.h>
int main (void)
{
char string[100] = "000000000000000000010000000000";
printf("%.8lx\n", strtol(string,0,2));
}
It you need to group it as bytes with space in between:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main (void)
{
char string[100] = "000000000000000000010000000000";
char byte_str[100];
sprintf(byte_str, "%.8lx\n", strtol(string,0,2));
for(size_t i=0; i<strlen(byte_str); i =2)
{
printf("%c%c ", byte_str[i], byte_str[i 1]);
}
}
This might not be the most efficient code but it literally took me a few minutes to write.
CodePudding user response：
If it an exercise to learn how to convert and split number into bytes without fancy library functions:
unsigned convert(const char * restrict str)
{
unsigned result = 0;
while(*str)
{
result *= 2;
result = *str == '1';
}
return result;
}
#define MASK ((1 << CHAR_BIT) - 1)
#define GETBYTE(val, index) (((val) >> ((sizeof(val) - (index) - 1) * CHAR_BIT)) & MASK)
void print(const unsigned val)
{
for(int index = 0; index < sizeof(val); index )
{
printf("x%c", GETBYTE(val, index), (index == sizeof(val) - 1) ? '\n' : ' ');
}
}
int main (void)
{
char string[100] = "000000000000000000010000000000";
unsigned val = convert(string);
printf("0xx\n", val);
print(val);
}