I use binary search to solve this problem and had trouble
with input
this input gots AC:
   double x;
   int j,t;
        fscanf(inf,"%lf",&x);
        L[i]=(int)(x*100.0+1e-9);
but this got WA9
        fscanf(inf,"%i.%i",&t,&j);
        L[i]=t*100+j;
 output in boyh programs was like this
    fprintf(outf,"%i.%0.2i\n",ANS/100,ANS%100);

possible reasons:
1. input data hasn't 2 digits after decimal point(maybe it have none digits and no point at all)
2. chacker is floating-point written program with do errors
and you have to do the same errors to AC.

this code is wrong
fscanf(inf,"%i.%i",&t,&j);
L[i]=t*100+j;

you must use scanf("%d", &x);
instead of scanf("%i", &x);
why ?
try to input "09"
%d reads it as 9, but %i reads some random thing