为什么会超时啊

#include <iostream>
using  namespace  std;
long long a[10000000],b[10000000];
int main ()
{
    double n,x=1;
    b[1]=1;
    cin>>n;
    for (int i=1;i<=n;i++) 
    {
        cin>>a[i];
    }
    for (int i=2;i<=n;i++)  
    {
      if (a[i] > a[i-1]) b[i] = b[i-1]+1;
      else b[i]=1;
      if (b[i]>x) x=b[i];
    }
    cout<<x;
    return 0;
}