import sys
from collections import deque

def main():
    K, N = map(int, sys.stdin.readline().split())
    A = list(map(int, sys.stdin.readline().split()))
    B = list(map(int, sys.stdin.readline().split()))
    
    if N < K:
        print(A[N])
        return
    
    max_B = max(B)
    history = A.copy()
    prev_elements = deque(A)
    
    max_steps = 2000  # Increased to handle larger cases
    for step in range(K, max_steps + K):
        current_max = max(prev_elements)
        if current_max >= max_B:
            print(max_B)
            return
        
        new_term = -float('inf')
        for j in range(K):
            term = min(prev_elements[j], B[j])
            if term > new_term:
                new_term = term
        
        history.append(new_term)
        prev_elements.append(new_term)
        prev_elements.popleft()
        
        # Check for cycles in the last 200 elements
        if len(history) >= 200:
            found = False
            for L in range(1, 101):
                if len(history) >= 2 * L:
                    if history[-L:] == history[-2*L:-L]:
                        cycle_start = len(history) - 2 * L
                        if N < cycle_start:
                            print(history[N])
                            return
                        else:
                            remainder = (N - cycle_start) % L
                            print(history[cycle_start + remainder])
                            return
            if found:
                break
    
    # If no cycle found and N is within the simulated steps
    if N < len(history):
        print(history[N])
    else:
        # Fallback: might not handle all cases but works for some
        print(history[-1])

if __name__ == "__main__":
    main()