Commit 0a56617

def NGRSimple(arr):

length = len(arr)

for i in range(0, length):

ans = -1

for j in range(i + 1, length):

if arr[i] < arr[j]:

ans = arr[j]

break

print(arr[j], "--", ans)

class Stack:

def __init__(self):

self.stack = []

def isEmpty(self):

return len(self.stack) == 0

def push(self, element):

self.stack.append(element)

def pop(self):

if self.isEmpty():

return -1

else:

return self.stack.pop()

def top(self):

return self.stack[-1]

def NGRStack(arr):

s = Stack()

ans = []

for i in range(len(arr) - 1, -1, -1):

if s.isEmpty():

ans.append(-1)

else:

if s.top() > arr[i]:

ans.append(s.top())

else:

while not s.isEmpty() and s.top() <= arr[i]:

s.pop()

if s.isEmpty():

ans.append(-1)

else:

ans.append(s.top())

s.push(arr[i])

ans.reverse()

return ans

def main():

arr = [11, 13, 21, 3]

NGRSimple(arr)

print(NGRStack(arr))

if __name__ == "__main__":

main()

# simple

def NGRSimple(arr: list):

length = len(arr)

for i in range(0, length):

ans = -1

for j in range(i + 1, length):

if arr[i] < arr[j]:

ans = arr[j]

break

print(arr[j], "--", ans)

class Stack:

def __init__(self):

self.stack = []

def isEmpty(self):

return len(self.stack) == 0

def push(self, element):

self.stack.append(element)

def pop(self):

if self.isEmpty():

return -1

else:

return self.stack.pop()

def top(self):

if self.isEmpty():

return -1

else:

return s[-1]

def NGRStack(arr):

s = Stack()

ans = []

for i in range(len(arr) - 1, -1, -1):

if s.isEmpty():

ans.append(-1)

else:

if s.top() > arr[i]:

ans.append(s.pop())

else:

while not s.isEmpty() and s.top <= arr[i]:

s.pop()

if s.isEmpty():

ans.append(-1)

else:

ans.append(ans.append(s.pop()))

s.push(arr[i])

def main():

arr = [11, 13, 21, 3]

NGRSimple(arr)

NGRStack(arr)

if __name__ == "__main__":

main()

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