add new solutions

solutions/0/q56/solution.go

@@ -0,0 +1,20 @@
+package q56
+
+import "slices"
+
+func merge(intervals [][]int) [][]int {
+	slices.SortFunc(intervals, func(a, b []int) int { return a[0] - b[0] })
+
+	p := 0
+	for i := 1; i < len(intervals); i++ {
+		if intervals[p][1] >= intervals[i][0] {
+			intervals[p][1] = max(intervals[p][1], intervals[i][1])
+		} else {
+			p++
+			intervals[p][0], intervals[p][1] = intervals[i][0], intervals[i][1]
+		}
+	}
+	return intervals[:min(p+1, len(intervals))]
+}
+
+var _ = merge