foo.cc: In function 'int main()':
foo.cc:10:11: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets(str1);
           ^
In file included from /usr/include/stdio.h:862:0,
                 from /usr/include/c++/7/cstdio:42,
                 from /usr/include/c++/7/ext/string_conversions.h:43,
                 from /usr/include/c++/7/bits/basic_string.h:6361,
                 from /usr/include/c++/7/string:52,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:232:1: note: declared here
 gets (char *__str)
 ^~~~
foo.cc:11:4: error: 'strlen' was not declared in this scope
  n=strlen(str1);
    ^~~~~~
foo.cc:11:4: note: suggested alternative: 'mbrlen'
  n=strlen(str1);
    ^~~~~~
    mbrlen
foo.cc:21:8: error: 'strcmp' was not declared in this scope
     if(strcmp(str1,str2)==0)
        ^~~~~~
foo.cc:21:8: note: suggested alternative: 'str2'
     if(strcmp(str1,str2)==0)
        ^~~~~~
        str2
foo.cc:10:6: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result [-Wunused-result]
  gets(str1);
  ~~~~^~~~~~

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