OJ Board

Wrong Answer
Plz some one help me.

#include<stdio.h>
float cout(char st[100000]);
void main()
{
float x,y;
float sum=0;
char st1[100000],st2[100000];
while(gets(st1))
{
x=cout(st1);
gets(st2);
y=cout(st2);
if(x>y)
sum=(float)(y*100/x);
else
sum=(float)(x*100/y);

printf("%.2f %c",sum ...