为什么会有segmentation fault

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int high, apple[20], c=0;
    memset(apple,0,sizeof(apple));
    for(int i=0;i<10;i++)
    {
        scanf("%d",apple[i]); 
    }
    scanf("%d",&high);
      for(int j=0;j<10;j++)
      {
        if(apple[j]<=(high+30))
            c++;
        }
    cout<<c;
    return 0;
}