OJ Board

Why getting WA???
Help Please........

#include <stdio.h>
#include <math.h>
#include <string.h>
long long int fib[777];
int fib_series(void)
{
fib[0]=1;
fib[1]=2;
int i=2;
while(fib[i-1]<pow(2,31))
{
fib =fib[i-1]+fib[i-2];
i++;
}
return i-1;
}
int main(void)
{
int a=0,n,t,r;
scanf("%d ...