# Python program to find the frequency of the elements which are common in a list of strings

Given list of strings. The task is to find the frequency of the elements which are common in all strings given in the list of strings.

**Examples:**

Input: test_list = ["gegek", "gfgk", "kingg"]Output: {'g': 2, 'k': 1}Explanation: g occurs twice in all Strings.Input: test_list = ["gefgek", "gfgk", "kinfgg"]Output: {'g': 2, 'k': 1, 'f' : 1}Explanation: f occurs once in all Strings.

**Method : Using reduce() + lambda + Counter()**

The combination of above functions can be used to solve this problem. In this, we perform the key role of counting using Counter() and lambda coupled with reduce() is used to perform intersection and extension of logic to all the strings respectively.

## Python3

`# Python3 code to demonstrate working of` `# Strings list intersection` `# Using reduce() + lambda + Counter()` `from` `functools ` `import` `reduce` `from` `collections ` `import` `Counter` `# initializing list` `test_list ` `=` `[` `"geek"` `, ` `"gfgk"` `, ` `"king"` `]` `# printing original list` `print` `(` `"The original list is : "` `+` `str` `(test_list))` `# using & operator to perform intersection` `res ` `=` `reduce` `(` `lambda` `a, b: a & b, (Counter(ele) ` `for` `ele ` `in` `test_list[` `1` `:]),` ` ` `Counter(test_list[` `0` `]))` `# printing result` `print` `(` `"String intersection and frequency : "` `+` `str` `(` `dict` `(res)))` |

**Output**

The original list is : ['geek', 'gfgk', 'king'] String intersection and frequency : {'g': 1, 'k': 1}

**Time Complexity: **O(n)

**Space Complexity: **O(n)