# Write a function to find the minimum number of platforms required for a railway/bus station.
def find_platform(arr, dep, n):
    arr.sort()
    dep.sort()
    plat_needed = 1
    result = 1
    i = 1
    j = 0
    while i < n and j < n:
        if arr[i] <= dep[j]:
            plat_needed += 1
            i += 1
        elif arr[i] > dep[j]:
            plat_needed -= 1
            j += 1
        if plat_needed > result:
            result = plat_needed
    return result
