Triangle Judgement — LeetCode 610 Python Solution

The problem

For every row, decide whether the three segment lengths can form a triangle and report the three lengths together with Yes or No. The Triangle table has one row per triple: x, y and z (int, the three segment lengths), with (x, y, z) as the primary key.

Example

Triangle table:

| x  | y  | z  |
| -- | -- | -- |
| 13 | 15 | 30 |
| 10 | 20 | 15 |
| 5  | 5  | 5  |
| 7  | 2  | 4  |

Result:

| x  | y  | z  | triangle |
| -- | -- | -- | -------- |
| 13 | 15 | 30 | No       |
| 10 | 20 | 15 | Yes      |
| 5  | 5  | 5  | Yes      |
| 7  | 2  | 4  | No       |

A triple works only when every pair of sides is longer than the third, which fails for 13, 15 and 30 because 13 plus 15 is under 30, and fails again for 7, 2 and 4.

Python solution

import pandas as pd

def triangle_judgement(triangle: pd.DataFrame) -> pd.DataFrame:
    df = triangle.copy()
    valid = (
        (df['x'] + df['y'] > df['z'])
        & (df['x'] + df['z'] > df['y'])
        & (df['y'] + df['z'] > df['x'])
    )
    df['triangle'] = valid.map({True: 'Yes', False: 'No'})
    return df[['x', 'y', 'z', 'triangle']]

Complexity

Related problems