/in/ex1.c: In function 'right':
/in/ex1.c:8:9: error: conversion to 'int' from 'size_t {aka long unsigned int}' may alter its value [-Werror=conversion]
 int len=strlen(src);
         ^~~~~~
/in/ex1.c:11:7: error: suggest parentheses around assignment used as truth value [-Werror=parentheses]
 while(*(q++)=*(p++));
       ^
/in/ex1.c: In function 'tolow':
/in/ex1.c:16:15: error: comparison between signed and unsigned integer expressions [-Werror=sign-compare]
  for(i = 0; i < strlen(a); i++){
               ^
/in/ex1.c:18:12: error: conversion to 'char' from 'int' may alter its value [-Werror=conversion]
    a[i] -= 'a';
            ^~~
/in/ex1.c: In function 'main':
/in/ex1.c:29:19: error: comparison between signed and unsigned integer expressions [-Werror=sign-compare]
      for(i = 0 ;i < strlen(a); i++){
                   ^
cc1: all warnings being treated as errors