1010. Pairs of Songs With Total Durations Divisible by 60 

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class Solution {
    public int numPairsDivisibleBy60(int[] time) {
        int pairs = 0;

        Map<Integer, Integer> maxDigitNumToMaxNumMap = new HashMap<>();
        for (int second : time) {
            second %= 60; // [0, 59]
            int count = maxDigitNumToMaxNumMap.getOrDefault(second == 0 ? 0 : 60 - second, 0);
            pairs += count;
            maxDigitNumToMaxNumMap.put(second, maxDigitNumToMaxNumMap.getOrDefault(second, 0) + 1);
        }

        return pairs;
    }
}

References

1010. Pairs of Songs With Total Durations Divisible by 60