string - Can someone explain this C code? -

can explain reverse sentence code me? how first , second looping works? what's point of each of them?

main(){     char arr[255], *p;      printf("enter string: ");     gets(arr);      for(p=arr; *p!='\0'; p++);      for(p--; p>=arr; p--){        printf("%c",*p);     } } 

input:

i love 

output:

uoy evol 

the code printing in reverse input array.

for(p=arr; *p!='\0'; p++); 

sets p last (relevant) element of array (the null character)

  for(p--; p>=arr; p--){       printf("%c",*p);     } 

starts last (none null) character , prints each 1 last first.

question you:
what happens if input array longet 255 chars? (answer below)

_{buffer overflow}