Pairs of Songs With Total Durations Divisible by 60

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Problem Statement

You are given a list of songs where the i ^th song has a duration of time[i] seconds.

Return the number of pairs of songs for which their total duration in seconds is divisible by 60 . Formally, we want the number of indices i , j such that i < j with (time[i] + time[j]) % 60 == 0 .

Examples

Example 1

Input: time = [30,20,150,100,40]
Output: 3
Three pairs have a total duration divisible by 60:
(time[0] = 30, time[2] = 150): total duration 180
(time[1] = 20, time[3] = 100): total duration 120
(time[1] = 20, time[4] = 40): total duration 60

Example 2

Input: time = [60,60,60]
Output: 3
All three pairs have a total duration of 120, which is divisible by 60.

Constraints

1 <= time.length <= 6 * 10 ^4

1 <= time[i] <= 500

🤔

Medium

Difficulty

Topic Info

ModuleDSA

CategoryArray

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