```
def main():

    n = int(input().strip())

    a = list(map(int, input().rstrip().split()))

    b = list(map(int, input().rstrip().split()))
    a.sort()
    b.sort()
    total=0
    i=0
    j=0
    while i!=len(a):
        while j!=len(b):
            # print('a[i]', a[i],'b[j]',b[j])  
            if a[i]<b[j]:
            # print('in a[i]<b[j]')
                i+=1
                break
            if a[i]==b[j]:
                total+=1
                i+=1
                j+=1
            # print('total is ',total)
                break
            else:
            # print('in else')
                j+=1
    if total==n:
        print(n)
    else:
        print(total+1)

main()

```

Input:

```
4
1 2 3 4
1 2 3 3

```

The program keeps asking for input even after i press the "enter" button on my keyboard. while for other types of input it works perfectly fine