permutation_sequence

Author: hitzzc

README.md

@@ -52,6 +52,7 @@ Golang solution for leetcode. For each problem, there is a simple *_test.go to t
 #### [55. jump game](https://github.com/hitzzc/go-leetcode/tree/master/jump_game)
 #### [58. length of last word](https://github.com/hitzzc/go-leetcode/tree/master/length_of_last_word)
 #### [59. spiral matrix II](https://github.com/hitzzc/go-leetcode/tree/master/spiral_matrix_II)
+#### [60. permutation sequence](https://github.com/hitzzc/go-leetcode/tree/master/permutation_sequence)
 
 
 

permutation_sequence/permutation_sequence.go

@@ -0,0 +1,21 @@
+package permutation_sequence
+
+func getPermutation(n int, k int) string {
+	if n == 0 {
+		return ""
+	}
+	data := make([]int, n)
+	data[0] = 1
+	iToS := []byte("123456789")
+	for i := 1; i < n; i++ {
+		data[i] = data[i-1] * i
+	}
+	ret := ""
+	k--
+	for i := n - 1; i >= 0; i-- {
+		ret += string(iToS[k/data[i]])
+		iToS = append(iToS[:k/data[i]], iToS[k/data[i]+1:]...)
+		k = k % data[i]
+	}
+	return ret
+}

permutation_sequence/permutation_sequence_test.go

@@ -0,0 +1,9 @@
+package permutation_sequence
+
+import (
+	"testing"
+)
+
+func TestGetPermutation(t *testing.T) {
+	println(getPermutation(3, 5))
+}