Three Simple Ways to Generate All 3‑Item Combinations in Python

1. Introduction

A fan asked how to generate all 3‑item combinations from a list of 10 Chinese character strings using Python. The combinatorial formula C(10,3)=120 confirms the expected number of combinations.

2. Solution Methods

Method 1 – itertools.combinations

from itertools import combinations
word = ['鲁班七号','鲁班','鲁班大师','甄姬','安琪拉','王昭君','韩信','孙悟空','程咬金','猪八戒']
res = [i for i in combinations(word, 3)]
print(res)
print(len(res))

Method 2 – Index‑based enumeration (image only)

This approach pre‑calculates the order of combinations before generating them.

Method 3 – List comprehension with slicing and index

word = ['鲁班七号','鲁班','鲁班大师','甄姬','安琪拉','王昭君','韩信','孙悟空','程咬金','猪八戒']
res = [[i, j, k] for i in word[:] for j in word[word.index(i)+1:] for k in word[word.index(j)+1:]]
print(res)
print(len(res))

The above code uses three nested loops implemented via list comprehension, achieving the same 120 combinations.

Another explicit loop version demonstrates the same logic:

res = []
for i in word[:]:
    for j in word[word.index(i)+1:]:
        for k in word[word.index(j)+1:]
            res.append([i, j, k])
print(res)

3. Conclusion

The three methods successfully solve the fan's combination problem, each producing the expected 120 results. For small data sets, any method works, but using itertools.combinations is the most concise and efficient for larger inputs.