foo.cc: In function 'int main()':
foo.cc:13:13: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
     gets(str);    
             ^
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:2:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:232:1: note: declared here
 gets (char *__str)
 ^~~~
foo.cc:17:13: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
             if(str[i]>='a'&&str[i]<='z')   
             ^~
foo.cc:19:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
                 i++;
                 ^
foo.cc:13:9: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result [-Wunused-result]
     gets(str);    
     ~~~~^~~~~
/tmp/ccpvtbUb.o: In function `main':
foo.cc:(.text.startup+0x27): warning: the `gets' function is dangerous and should not be used.

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