foo.cc: In function 'int main()':
foo.cc:6:15: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   while(gets(s)){
               ^
In file included from /usr/include/stdio.h:862:0,
                 from /usr/include/c++/7/cstdio:42,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:46,
                 from foo.cc:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:232:1: note: declared here
 gets (char *__str)
 ^~~~
foo.cc:8:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<strlen(s);i++){
                 ~^~~~~~~~~~
foo.cc:5:7: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
   int ans;
       ^~~
/tmp/ccOX9P8g.o: In function `main':
foo.cc:(.text.startup+0x31): warning: the `gets' function is dangerous and should not be used.

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