Question

3. Look up the man pages for the following string functions from the C standard library, and write implementations of each:

• strcmp()

Please explain your answer, thank you

Answer 1

Solution

#include <stdio.h>

int strcmp(const char *S1, const char *S2)
{
while (*S1)
{
if (*S1!= *S2)
break;

S1++;
S2++;
}

return *(const unsigned char*)S1- *(const unsigned char*)S2;
}

int main()
{
char *A = "Student";
char *B = "Stand";

int cmp = strcmp(A, B);

if (cmp > 0)
printf("%s is greater than %s. Character in %s is lexicographically after the character of %s",A,B,A,B);
else if (cmp < 0)
printf("%s is less than %s. Character in %s is lexicographically before the character of %s",A,B,A,B);
else
printf("%s is equal to %s",A,B);
return 0;
}

Code Screenshot

Output