# playground
import numpy as np
import pandas as pd
# arr = np.array([11, 12, 13, 14, 15, 16, 17, 15, 11, 12, 14, 15, 16, 17])
# result = np.where(arr == 15)

# print(arr[result
# data = pd.DataFrame(columns=list(range(10)))
# data1= pd.DataFrame([[1,2,3]])
# data = data.append(data1,ignore_index = True)
# data = data.append(data1,ignore_index = True)
# data = data.append([[1,4,7,9]],ignore_index = True)
# print(data
a = [1,2,4,8]
b = [2,4,6,10]
c = (np.array(a)+np.array(b))/2
print(c)