foo.c: In function 'Concat':
foo.c:7:3: error: 's' undeclared (first use in this function)
7 | s[i-2]=a[0];
| ^
foo.c:7:3: note: each undeclared identifier is reported only once for each function it appears in
foo.c:6:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
6 | for(i=0;str[i]!='\0';i++)
| ^~~
foo.c:8:3: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
8 | s[i-2]='\0';
| ^
foo.c: In function 'main':
foo.c:14:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
14 | gets(s1);
| ^~~~
In file included from /usr/include/stdio.h:867,
from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:1: note: declared here
235 | gets (char *__str)
| ^~~~
foo.c:15:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
15 | gets(s2);
| ^~~~
In file included from /usr/include/stdio.h:867,
from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:235:1: note: declared here
235 | gets (char *__str)
| ^~~~
foo.c: In function 'Concat':
foo.c:10:1: warning: control reaches end of non-void function [-Wreturn-type]
10 | }
| ^
foo.c: In function 'main':
foo.c:14:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
14 | gets(s1);
| ^~~~~~~~
foo.c:15:2: warning: ignoring return value of 'gets', declared with attribute warn_unused_result [-Wunused-result]
15 | gets(s2);
| ^~~~~~~~
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