c-gcc, 95 bytes

Result

WA

Code [DL]

char c,s[100],i;main(){read(0,&s,100);for(c=47;58-c++;)for(i=99;i--+1;write(1,&s[i],s[i]==c));}

stdin

6425752821849667160863126100125243798897416294017707991587618658414323809108859152107617522973254123

stdout

000000001111111111111112222222222222333334444444455555555566666666667777777777788888888888999999999

stderr

/volume/CODE.c:1:17: warning: return type defaults to ‘int’ [-Wimplicit-int]
 char c,s[100],i;main(){read(0,&s,100);for(c=47;58-c++;)for(i=99;i--+1;write(1,&s[i],s[i]==c));}
                 ^
/volume/CODE.c: In function ‘main’:
/volume/CODE.c:1:24: warning: implicit declaration of function ‘read’ [-Wimplicit-function-declaration]
 char c,s[100],i;main(){read(0,&s,100);for(c=47;58-c++;)for(i=99;i--+1;write(1,&s[i],s[i]==c));}
                        ^
/volume/CODE.c:1:71: warning: implicit declaration of function ‘write’ [-Wimplicit-function-declaration]
 char c,s[100],i;main(){read(0,&s,100);for(c=47;58-c++;)for(i=99;i--+1;write(1,&s[i],s[i]==c));}
                                                                       ^
/volume/CODE.c:1:81: warning: array subscript has type ‘char’ [-Wchar-subscripts]
 char c,s[100],i;main(){read(0,&s,100);for(c=47;58-c++;)for(i=99;i--+1;write(1,&s[i],s[i]==c));}
                                                                                 ^
/volume/CODE.c:1:86: warning: array subscript has type ‘char’ [-Wchar-subscripts]
 char c,s[100],i;main(){read(0,&s,100);for(c=47;58-c++;)for(i=99;i--+1;write(1,&s[i],s[i]==c));}
                                                                                      ^

strace