From 0e4bb92726111a9b18962e454d46a85ebde9cef8 Mon Sep 17 00:00:00 2001
From: Matej Focko <me@mfocko.xyz>
Date: Sun, 4 Aug 2024 14:36:18 +0200
Subject: [PATCH] =?UTF-8?q?go:=20add=20=C2=AB1508.=20Range=20Sum=20of=20So?=
 =?UTF-8?q?rted=20Subarray=20Sums=C2=BB?=
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Signed-off-by: Matej Focko <me@mfocko.xyz>
---
 go/range-sum-of-sorted-subarray-sums.go | 43 +++++++++++++++++++++++++
 1 file changed, 43 insertions(+)
 create mode 100644 go/range-sum-of-sorted-subarray-sums.go

diff --git a/go/range-sum-of-sorted-subarray-sums.go b/go/range-sum-of-sorted-subarray-sums.go
new file mode 100644
index 0000000..6fed418
--- /dev/null
+++ b/go/range-sum-of-sorted-subarray-sums.go
@@ -0,0 +1,43 @@
+package main
+
+import (
+	"cmp"
+
+	pq "github.com/emirpasic/gods/v2/queues/priorityqueue"
+)
+
+const MOD int = 1_000_000_007
+
+type Sum struct {
+	index int
+	sum   int
+}
+
+func cmpSum(a, b Sum) int {
+	return cmp.Compare(a.sum, b.sum)
+}
+
+func rangeSum(nums []int, n int, left int, right int) int {
+	q := pq.NewWith[Sum](cmpSum)
+
+	for i, num := range nums {
+		q.Enqueue(Sum{index: i, sum: num})
+	}
+
+	total := 0
+	for i := 1; i <= right; i++ {
+		s, _ := q.Dequeue()
+
+		if i >= left {
+			total = (total + s.sum) % MOD
+		}
+
+		if s.index < n-1 {
+			s.index++
+			s.sum += nums[s.index]
+			q.Enqueue(s)
+		}
+	}
+
+	return total
+}