From c7b0da5b641787f9ef2a373a7d773628c8128537 Mon Sep 17 00:00:00 2001
From: ductnn <trannhuduc531998@gmail.com>
Date: Tue, 26 Mar 2024 10:13:35 +0700
Subject: [PATCH] add sol

---
 leetcode/41.FirstMissingPositive/sol.go | 27 +++++++++++++++++++++++++
 1 file changed, 27 insertions(+)
 create mode 100644 leetcode/41.FirstMissingPositive/sol.go

diff --git a/leetcode/41.FirstMissingPositive/sol.go b/leetcode/41.FirstMissingPositive/sol.go
new file mode 100644
index 0000000..647f6aa
--- /dev/null
+++ b/leetcode/41.FirstMissingPositive/sol.go
@@ -0,0 +1,27 @@
+// https://leetcode.com/problems/first-missing-positive
+
+package main
+
+import "fmt"
+
+func firstMissingPositive(nums []int) int {
+	m := make(map[int]bool)
+
+	for _, num := range nums {
+		if num > 0 {
+			m[num] = true
+		}
+	}
+
+	for i := 1; ; i++ {
+		if !m[i] {
+			return i
+		}
+	}
+}
+
+func main() {
+	nums := []int{3, 4, -1, 1}
+
+	fmt.Println(firstMissingPositive(nums))
+}