foo.c: In function 'main':
foo.c:8:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
  gets(str);
  ^~~~
In file included from /usr/include/stdio.h:862:0,
                 from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:232:1: note: declared here
 gets (char *__str)
 ^~~~
foo.c:15:18: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    if(str[i]>='a'&&str[i]<'w'||str[i]>='A'&&str[i]<'W')
       ~~~~~~~~~~~^~~~~~~~~~~~
foo.c:18:19: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     if(str[i]>='w'&&str[i]<='z'||str[i]>='W'&&str[i]<='Z')
        ~~~~~~~~~~~^~~~~~~~~~~~~
foo.c:25:18: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    if(str[i]>='a'&&str[i]<='w'||str[i]>='A'&&str[i]<='W')
       ~~~~~~~~~~~^~~~~~~~~~~~~
foo.c:28:18: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
     if(str[i]>'w'&&str[i]<='z'||str[i]>'W'&&str[i]<='Z')
        ~~~~~~~~~~^~~~~~~~~~~~~
foo.c:8:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
  gets(str);
  ^~~~~~~~~
foo.c:10:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&k);
  ^~~~~~~~~~~~~~
/tmp/cc5i9L9H.o: In function `main':
foo.c:(.text.startup+0x2f): warning: the `gets' function is dangerous and should not be used.

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