updates

2 files changed, 36 insertions, 0 deletions

diff --git a/7/go.mod b/7/go.mod
new file mode 100644
index 0000000..b924aab
--- /dev/null
+++ b/7/go.mod
@@ -0,0 +1,3 @@
+module 7
+
+go 1.17
diff --git a/7/main.go b/7/main.go
new file mode 100644
index 0000000..7bf96b8
--- /dev/null
+++ b/7/main.go
@@ -0,0 +1,33 @@
+package main
+
+import "fmt"
+
+func reverse(x int) int {
+	var res int
+	var negative bool
+	if x < 0 {
+		negative = true
+		x = x * -1
+	}
+	for x > 0 {
+		digit := x - ((x / 10) * 10)
+		res = res*10 + digit
+		if res > (0x1 << 31) {
+			return 0
+		}
+		x = x / 10
+	}
+
+	if negative {
+		return res * -1
+	}
+	return res
+}
+
+func main() {
+	fmt.Println(reverse(123))
+	fmt.Println(reverse(-123))
+	fmt.Println(reverse(120))
+	fmt.Println(reverse(1534236469))
+
+}