#0073

Days Between Dates

EasyPython15 min10 XP

Problem

Given two strings in YYYY-MM-DD format, return the absolute number of days between them.

Why This Matters

Date arithmetic appears in retention, subscriptions, SLAs, time-series features, and reporting.

Function Signature

def days_between(start, end):

Examples

Example 1

Input"2026-01-01", "2026-01-10"

Output9

The difference between Jan 1 and Jan 10 is nine full days.

Constraints

Inputs are valid ISO date strings.
Return an absolute difference.
Use datetime/date parsing, not manual month arithmetic.

CodePython

def days_between(start, end):
    """
    Input example: "2026-01-01", "2026-01-10"
    Return: 9
    Return the value from the function so the tests can compare it. Do not print unless the prompt asks.
    """
    # write your code here
    return 0

def days_between(start, end):
    """
    Input example: "2026-01-01", "2026-01-10"
    Return: 9
    Return the value from the function so the tests can compare it. Do not print unless the prompt asks.
    """
    # write your code here
    return 0

Visible browser tests run here when available.

Testcases2 visible / 3 hidden categories

Forward dates

Input"2026-01-01", "2026-01-10"

Expected9

Subtracting date objects handles calendar details.

Reverse dates

Input"2026-01-10", "2026-01-01"

Expected9

The function returns absolute difference.

Hidden Test Categories

same dateleap year datemonth boundary