c-gcc, 126 bytes

Result

WA

Duration

593ms

Code [DL]

b,c,d;main(){char i[101];b=scanf("%s",&i);for(d=b;b;b--){if(i[d-b]-48>9){for(c=i[d-b+1]-48<10?:1;c;c--)printf("%c",i[d-b]);}}}

stdin

r5j8z4p7p3f4h6x5y6p2q7u6b6g8o4h9ad5g5g9w6m4w9c2r8e3h5d9c5n3k7o6p7b2i8k7t9uqkm5y8rd5k9j8v9l7p3s8

stdout

r

stderr

/tmp/code.c:1:1: warning: data definition has no type or storage class
 b,c,d;main(){char i[101];b=scanf("%s",&i);for(d=b;b;b--){if(i[d-b]-48>9){for(c=i[d-b+1]-48<10?:1;c;c--)printf("%c",i[d-b]);}}}
 ^
/tmp/code.c:1:1: warning: type defaults to 'int' in declaration of 'b' [-Wimplicit-int]
/tmp/code.c:1:3: warning: type defaults to 'int' in declaration of 'c' [-Wimplicit-int]
 b,c,d;main(){char i[101];b=scanf("%s",&i);for(d=b;b;b--){if(i[d-b]-48>9){for(c=i[d-b+1]-48<10?:1;c;c--)printf("%c",i[d-b]);}}}
   ^
/tmp/code.c:1:5: warning: type defaults to 'int' in declaration of 'd' [-Wimplicit-int]
 b,c,d;main(){char i[101];b=scanf("%s",&i);for(d=b;b;b--){if(i[d-b]-48>9){for(c=i[d-b+1]-48<10?:1;c;c--)printf("%c",i[d-b]);}}}
     ^
/tmp/code.c:1:7: warning: return type defaults to 'int' [-Wimplicit-int]
 b,c,d;main(){char i[101];b=scanf("%s",&i);for(d=b;b;b--){if(i[d-b]-48>9){for(c=i[d-b+1]-48<10?:1;c;c--)printf("%c",i[d-b]);}}}
       ^~~~
/tmp/code.c: In function 'main':
/tmp/code.c:1:28: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
 b,c,d;main(){char i[101];b=scanf("%s",&i);for(d=b;b;b--){if(i[d-b]-48>9){for(c=i[d-b+1]-48<10?:1;c;c--)printf("%c",i[d-b]);}}}
                            ^~~~~
/tmp/code.c:1:28: warning: incompatible implicit declaration of built-in function 'scanf'
/tmp/code.c:1:28: note: include '<stdio.h>' or provide a declaration of 'scanf'
+#include <stdio.h>
 b,c,d;main(){char i[101];b=scanf("%s",&i);for(d=b;b;b--){if(i[d-b]-48>9){for(c=i[d-b+1]-48<10?:1;c;c--)printf("%c",i[d-b]);}}}
                            ^~~~~
/tmp/code.c:1:36: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[101]' [-Wformat=]
 b,c,d;main(){char i[101];b=scanf("%s",&i);for(d=b;b;b--){if(i[d-b]-48>9){for(c=i[d-b+1]-48<10?:1;c;c--)printf("%c",i[d-b]);}}}
                                   ~^  ~~
/tmp/code.c:1:95: warning: the omitted middle operand in ?: will always be 'true', suggest explicit middle operand [-Wparentheses]
 b,c,d;main(){char i[101];b=scanf("%s",&i);for(d=b;b;b--){if(i[d-b]-48>9){for(c=i[d-b+1]-48<10?:1;c;c--)printf("%c",i[d-b]);}}}
                                                                                               ^
/tmp/code.c:1:104: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
 b,c,d;main(){char i[101];b=scanf("%s",&i);for(d=b;b;b--){if(i[d-b]-48>9){for(c=i[d-b+1]-48<10?:1;c;c--)printf("%c",i[d-b]);}}}
                                                                                                        ^~~~~~
/tmp/code.c:1:104: warning: incompatible implicit declaration of built-in function 'printf'
/tmp/code.c:1:104: note: include '<stdio.h>' or provide a declaration of 'printf'

strace