foo.cc: In function 'int main()':
foo.cc:5:11: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
     gets(a);
           ^
In file included from /usr/include/stdio.h:862:0,
                 from /usr/include/c++/7/cstdio:42,
                 from foo.cc:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:232:1: note: declared here
 gets (char *__str)
 ^~~~
foo.cc:6:11: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
     gets(b);
           ^
In file included from /usr/include/stdio.h:862:0,
                 from /usr/include/c++/7/cstdio:42,
                 from foo.cc:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:232:1: note: declared here
 gets (char *__str)
 ^~~~
foo.cc:21:33: warning: left operand of comma operator has no effect [-Wunused-value]
             for (j = n,k = 0; j <= i, a[k] != '\0'; j++, k++) {
                               ~~^~~~
foo.cc:9:20: warning: unused variable 'l' [-Wunused-variable]
     int i, s, n=0, l, j, ss=0, k, rec;
                    ^
foo.cc:9:35: warning: variable 'rec' set but not used [-Wunused-but-set-variable]
     int i, s, n=0, l, j, ss=0, k, rec;
                                   ^~~
foo.cc:5:9: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result [-Wunused-result]
     gets(a);
     ~~~~^~~
foo.cc:6:9: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result [-Wunused-result]
     gets(b);
     ~~~~^~~
/tmp/cc3VpVNk.o: In function `main':
foo.cc:(.text.startup+0x31): warning: the `gets' function is dangerous and should not be used.

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