Change the contents of the array "Student a Am I" to "I am a student"

There is a character array whose contents are: "Student a am i", please change the contents of the array to "i am a student". Requirement: library functions cannot be used. Only a limited space can be opened (the number of spaces is independent of the length of the string). #include <stdio.h> #include <assert.h>int my_len (char *str) {        int count=0;assert (str); while (*STR) {   count++;   str++;} Return count;} Void  reverse (char *start,char *end) {   while (start<end)     {      char tmp=*start;  *start=*end;  *end=tmp;   start++;  end--;   }}void rev (char *s) {  int len =my_len (s);   char *start=s;  char *end=s+len-1;  reverse (start,end);   while (*s)   {     start=s; while ((*s!= '   ') && (* S!= '))  {   s++; } end=s-1; reverse (start,end);  if (*s ==  '   ')       s++;  }  }int main () {char s[] = "Student a am i"; Rev (s);p rintf ("%s\n", s); System ("pause");    return 0;}

Change the contents of the array "Student a Am I" to "I am a student"