c-gcc, 78 bytes

Result

WA

Code [DL]

f()(int*a){return*a-*1[&a];}int main(p,s){gets(s);qsort(s,100,1,f);puts(s);}

stdin

5836974583174154705306531873702974840953304512168046548796932053973025722760618969961237537636548972

stdout

stderr

/volume/CODE.c:1:1: error: ‘f’ declared as function returning a function
 f()(int*a){return*a-*1[&a];}int main(p,s){gets(s);qsort(s,100,1,f);puts(s);}
 ^
/volume/CODE.c:1:1: warning: return type defaults to ‘int’ [-Wimplicit-int]
/volume/CODE.c: In function ‘f’:
/volume/CODE.c:1:19: error: ‘a’ undeclared (first use in this function)
 f()(int*a){return*a-*1[&a];}int main(p,s){gets(s);qsort(s,100,1,f);puts(s);}
                   ^
/volume/CODE.c:1:19: note: each undeclared identifier is reported only once for each function it appears in
/volume/CODE.c: In function ‘main’:
/volume/CODE.c:1:33: warning: type of ‘p’ defaults to ‘int’ [-Wimplicit-int]
 f()(int*a){return*a-*1[&a];}int main(p,s){gets(s);qsort(s,100,1,f);puts(s);}
                                 ^
/volume/CODE.c:1:33: warning: type of ‘s’ defaults to ‘int’ [-Wimplicit-int]
/volume/CODE.c:1:43: warning: implicit declaration of function ‘gets’ [-Wimplicit-function-declaration]
 f()(int*a){return*a-*1[&a];}int main(p,s){gets(s);qsort(s,100,1,f);puts(s);}
                                           ^
/volume/CODE.c:1:51: warning: implicit declaration of function ‘qsort’ [-Wimplicit-function-declaration]
 f()(int*a){return*a-*1[&a];}int main(p,s){gets(s);qsort(s,100,1,f);puts(s);}
                                                   ^
/volume/CODE.c:1:68: warning: implicit declaration of function ‘puts’ [-Wimplicit-function-declaration]
 f()(int*a){return*a-*1[&a];}int main(p,s){gets(s);qsort(s,100,1,f);puts(s);}
                                                                    ^
/volume/CODE.c: In function ‘f’:
/volume/CODE.c:1:1: warning: control reaches end of non-void function [-Wreturn-type]
 f()(int*a){return*a-*1[&a];}int main(p,s){gets(s);qsort(s,100,1,f);puts(s);}
 ^
/home/esolang/bin/c-gcc: line 4: /tmp/code: No such file or directory

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