n = int(input())
s, t = map(int, input().split())
a = list(map(int, input().split()))

used = [False] * (n + 1)  # 1-based indexing
used[s] = True
used[t] = True

x = a[s-1]
y = a[t-1]

# 315's territory boundaries
l1 = r1 = s
# 8128's territory boundaries
l2 = r2 = t

turn = 0  # 0 for 315, 1 for 8128

while True:
    all_used = True
    for i in range(1, n+1):
        if not used[i]:
            all_used = False
            break
    if all_used:
        break
    
    if turn % 2 == 0:
        # 315's turn
        left = l1 - 1 if l1 > 1 else n
        right = r1 + 1 if r1 < n else 1
        candidates = []
        if not used[left]:
            candidates.append((a[left-1], left, 'left'))
        if not used[right]:
            candidates.append((a[right-1], right, 'right'))
        if candidates:
            candidates.sort(reverse=True, key=lambda x: x[0])
            val, pos, dir = candidates[0]
            x += val
            used[pos] = True
            if dir == 'left':
                l1 = pos
            else:
                r1 = pos
    else:
        # 8128's turn
        left = l2 - 1 if l2 > 1 else n
        right = r2 + 1 if r2 < n else 1
        candidates = []
        if not used[left]:
            candidates.append((a[left-1], left, 'left'))
        if not used[right]:
            candidates.append((a[right-1], right, 'right'))
        if candidates:
            candidates.sort(reverse=True, key=lambda x: x[0])
            val, pos, dir = candidates[0]
            y += val
            used[pos] = True
            if dir == 'left':
                l2 = pos
            else:
                r2 = pos
    
    turn += 1

print(x - y)