c-gcc, 101 bytes

Result

WA

Duration

790ms

Code [DL]

b;char*c,d[99];main(){gets(c);while(gets(d))puts(c);for(;d[++b]-75;);for(;c[b]-84;)++c[b++];puts(c);}

stdin

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                        K                         

stdout

stderr

/tmp/code.c:1:1: warning: data definition has no type or storage class
 b;char*c,d[99];main(){gets(c);while(gets(d))puts(c);for(;d[++b]-75;);for(;c[b]-84;)++c[b++];puts(c);}
 ^
/tmp/code.c:1:1: warning: type defaults to 'int' in declaration of 'b' [-Wimplicit-int]
/tmp/code.c:1:16: warning: return type defaults to 'int' [-Wimplicit-int]
 b;char*c,d[99];main(){gets(c);while(gets(d))puts(c);for(;d[++b]-75;);for(;c[b]-84;)++c[b++];puts(c);}
                ^~~~
/tmp/code.c: In function 'main':
/tmp/code.c:1:23: warning: implicit declaration of function 'gets' [-Wimplicit-function-declaration]
 b;char*c,d[99];main(){gets(c);while(gets(d))puts(c);for(;d[++b]-75;);for(;c[b]-84;)++c[b++];puts(c);}
                       ^~~~
/tmp/code.c:1:45: warning: implicit declaration of function 'puts' [-Wimplicit-function-declaration]
 b;char*c,d[99];main(){gets(c);while(gets(d))puts(c);for(;d[++b]-75;);for(;c[b]-84;)++c[b++];puts(c);}
                                             ^~~~
Segmentation fault (core dumped)

strace