Buggy python submission (verdict: Runtime Error):
N = int(input())
A = [int(a) for a in input().split()]

def chk(k):
    if k == 1:
        for i in range(1, N):
            if A[i] <= A[i-1]: return 0
        return 1
    
    X = [(0, 0)]
    def add(x):
        if x <= 0: return 0
        if a > X[-1][0]:
            X.append((a, 0))
        elif a == X[-1][0]:
            if X[-1][1] + 1 < k:
                X[-1] = (X[-1][0], X[-1][1] + 1)
            else:
                add(x-1)
        else:
            while X[-1][0] > a:
                X.pop()
            if a > X[-1][0]:
                X.append((a, 1))
            elif a == X[-1][0]:
                if X[-1][1] + 1 < k:
                    X[-1] = (X[-1][0], X[-1][1] + 1)
                else:
                    add(x-1)
        return 1
    
    for a in A:
        c = add(a)
        if c == 0: return 0
    return 1

l, r = 0, 1 << 18
while r - l > 1:
    m = (l + r) // 2
    if chk(m):
        r = m
    else:
        l = m

print(r)

Fixed submission:
N = int(input())
A = [int(a) for a in input().split()]

def chk(k):
    if k == 1:
        for i in range(1, N):
            if A[i] <= A[i-1]: return 0
        return 1
    
    X = [(0, 0)]
    def add(x, y):
        if x <= 0: return 0
        if x > X[-1][0]:
            X.append((x, 0 if x == y else 1))
        elif x == X[-1][0]:
            if X[-1][1] + 1 < k:
                X[-1] = (X[-1][0], X[-1][1] + 1)
            else:
                if add(x-1, y) == 0: return 0
        else:
            while X[-1][0] > x:
                X.pop()
            if x > X[-1][0]:
                X.append((x, 1))
            elif x == X[-1][0]:
                if X[-1][1] + 1 < k:
                    X[-1] = (X[-1][0], X[-1][1] + 1)
                else:
                    if add(x-1, y) == 0: return 0
        if X[-1][0] < y: X.append((y, 0))
        return 1
    
    for a in A:
        if add(a, a) == 0: return 0
    return 1

l, r = 0, 1 << 18
while r - l > 1:
    m = (l + r) // 2
    if chk(m):
        r = m
    else:
        l = m

print(r)

Buggy python submission (verdict: Runtime Error):
N = int(input())
A = [int(a) for a in input().split()]

def chk(k):
    if k == 1:
        for i in range(1, N):
            if A[i] <= A[i-1]: return 0
        return 1
    
    X = [(0, 0)]
    def add(x):
        if x <= 0: return 0
        if a > X[-1][0]:
            X.append((a, 0))
        elif a == X[-1][0]:
            if X[-1][1] + 1 < k:
                X[-1] = (X[-1][0], X[-1][1] + 1)
            else:
                add(x-1)
        else:
            while X[-1][0] > a:
                X.pop()
            if a > X[-1][0]:
                X.append((a, 1))
            elif a == X[-1][0]:
                if X[-1][1] + 1 < k:
                    X[-1] = (X[-1][0], X[-1][1] + 1)
                else:
                    add(x-1)
    for a in A:
        c = add(a)
        if c == 0: return 0
    return 1

l, r = 0, 1 << 18
while r - l > 1:
    m = (l + r) // 2
    if chk(m):
        r = m
    else:
        l = m

print(r)

Fixed submission:
N = int(input())
A = [int(a) for a in input().split()]

def chk(k):
    if k == 1:
        for i in range(1, N):
            if A[i] <= A[i-1]: return 0
        return 1
    
    X = [(0, 0)]
    def add(x, y):
        if x <= 0: return 0
        if x > X[-1][0]:
            X.append((x, 0 if x == y else 1))
        elif x == X[-1][0]:
            if X[-1][1] + 1 < k:
                X[-1] = (X[-1][0], X[-1][1] + 1)
            else:
                if add(x-1, y) == 0: return 0
        else:
            while X[-1][0] > x:
                X.pop()
            if x > X[-1][0]:
                X.append((x, 1))
            elif x == X[-1][0]:
                if X[-1][1] + 1 < k:
                    X[-1] = (X[-1][0], X[-1][1] + 1)
                else:
                    if add(x-1, y) == 0: return 0
        if X[-1][0] < y: X.append((y, 0))
        return 1
    
    for a in A:
        if add(a, a) == 0: return 0
    return 1

l, r = 0, 1 << 18
while r - l > 1:
    m = (l + r) // 2
    if chk(m):
        r = m
    else:
        l = m

print(r)

Buggy python submission (verdict: Time Limit Exceeded):
N = int(input())
A = [int(a) for a in input().split()]

l = 0
r = 2 * 10**5
while r-l >= 2:
    m = l + (r-l) //2
    X = {}
    for i in range(1,N):
        try:
            if A[i] <= A[i-1]:
                if A[i] < A[i-1]:
                    for j in X:
                        if j > A[i]:
                            X[j] = 0
                            # del X[j]
                if A[i] in X:
                    X[A[i]] += 1
                    k = A[i]
                    while k in X and X[k] >= m:
                        X[k] = 0
                        if k-1 in X:
                            X[k-1] += 1
                        else:
                            X[k-1] = 1
                        k -= 1
                        if k <= 0:
                            raise Exception
                else:
                    if m == 1:
                        raise Exception
                    X[A[i]] = 1
                    
        except:
            l = m
            break
    else:
        r = m
print(r)


Fixed submission:
N = int(input())
A = [int(a) for a in input().split()]

def chk(k):
    if k == 1:
        for i in range(1, N):
            if A[i] <= A[i-1]: return 0
        return 1
    
    X = [(0, 0)]
    def add(x, y):
        if x <= 0: return 0
        if x > X[-1][0]:
            X.append((x, 0 if x == y else 1))
        elif x == X[-1][0]:
            if X[-1][1] + 1 < k:
                X[-1] = (X[-1][0], X[-1][1] + 1)
            else:
                if add(x-1, y) == 0: return 0
        else:
            while X[-1][0] > x:
                X.pop()
            if x > X[-1][0]:
                X.append((x, 1))
            elif x == X[-1][0]:
                if X[-1][1] + 1 < k:
                    X[-1] = (X[-1][0], X[-1][1] + 1)
                else:
                    if add(x-1, y) == 0: return 0
        if X[-1][0] < y: X.append((y, 0))
        return 1
    
    for a in A:
        if add(a, a) == 0: return 0
    return 1

l, r = 0, 1 << 18
while r - l > 1:
    m = (l + r) // 2
    if chk(m):
        r = m
    else:
        l = m

print(r)

Buggy python submission (verdict: Time Limit Exceeded):
N = int(input())
A = [int(a) for a in input().split()]

l = 0
r = 2 * 10**5
while r-l >= 2:
    m = l + (r-l) //2
    X = {}
    for i in range(1,N):
        try:
            if A[i] <= A[i-1]:
                if A[i] < A[i-1]:
                    for j in X:
                        if j > A[i]:
                            X[j] = 0
                            # del X[j]
                if A[i] in X:
                    X[A[i]] += 1
                    k = A[i]
                    while k in X and X[k] >= m:
                        X[k] = 0
                        if k-1 in X:
                            X[k-1] += 1
                        else:
                            X[k-1] = 1
                        k -= 1
                        if k <= 0:
                            raise Exception
                else:
                    if m == 1:
                        raise Exception
                    X[A[i]] = 1
                    
        except:
            l = m
            break
    else:
        r = m
print(r)


Fixed submission:
N = int(input())
A = [int(a) for a in input().split()]

def chk(k):
    if k == 1:
        for i in range(1, N):
            if A[i] <= A[i-1]: return 0
        return 1
    
    X = [(0, 0)]
    def add(x, y):
        if x <= 0: return 0
        if x > X[-1][0]:
            X.append((x, 0 if x == y else 1))
        elif x == X[-1][0]:
            if X[-1][1] + 1 < k:
                X[-1] = (X[-1][0], X[-1][1] + 1)
            else:
                if add(x-1, y) == 0: return 0
        else:
            while X[-1][0] > x:
                X.pop()
            if x > X[-1][0]:
                X.append((x, 1))
            elif x == X[-1][0]:
                if X[-1][1] + 1 < k:
                    X[-1] = (X[-1][0], X[-1][1] + 1)
                else:
                    if add(x-1, y) == 0: return 0
        if X[-1][0] < y: X.append((y, 0))
        return 1
    
    for a in A:
        if add(a, a) == 0: return 0
    return 1

l, r = 0, 1 << 18
while r - l > 1:
    m = (l + r) // 2
    if chk(m):
        r = m
    else:
        l = m

print(r)