Python – 检查第 K 个索引元素是否唯一

给定一个字符串列表，检查是否所有第 K 个索引元素都是唯一的。

Input : test_list = [“gfg”, “best”, “for”, “geeks”], K = 1
Output : False
Explanation : e occurs as 1st index in both best and geeks.

Input : test_list = [“gfg”, “best”, “geeks”], K = 2
Output : True
Explanation : g, s, e, all are unique.

方法#1：使用循环

这是解决这个问题的粗暴方法。在此，我们对每个字符串进行迭代，并在重复任何元素时标记关闭，并返回 false。

Python3

# Python3 code to demonstrate working of 
# Check if Kth index elements are unique
# Using loop
  
# initializing list
test_list = ["gfg", "best", "for", "geeks"] 
  
# printing original list
print("The original list is : " + str(test_list))
  
# initializing K 
K = 2
  
res = []
flag = True
for ele in test_list:
      
    # checking if element is repeated
    if ele[K] in res:
        flag = False
        break
    else:
        res.append(ele[K])
          
# printing result 
print("Is Kth index all unique : " + str(flag))

输出

The original list is : ['gfg', 'best', 'for', 'geeks']
Is Kth index all unique : True

方法 #2：使用 Counter() + all()

在此，我们计算每个字符的频率。在第 K 个索引处，all() 用于检查 Counter 是否小于 2。

Python3

# Python3 code to demonstrate working of 
# Check if Kth index elements are unique
# Using Counter() + all()
from collections import Counter
  
# initializing list
test_list = ["gfg", "best", "for", "geeks"] 
  
# printing original list
print("The original list is : " + str(test_list))
  
# initializing K 
K = 2
  
# getting count of each Kth index item
count = Counter(sub[K] for sub in test_list)
  
# extracting result 
res = all(val < 2 for val in count.values())
          
# printing result 
print("Is Kth index all unique : " + str(res))

输出

The original list is : ['gfg', 'best', 'for', 'geeks']
Is Kth index all unique : True