119 accepted & finish

Author: aQua

Algorithms/0119.pascals-triangle-ii/README.md

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+# [119. Pascal's Triangle II](https://leetcode.com/problems/pascals-triangle-ii/)
+
+## 题目
+Given an index k, return the kth row of the Pascal's triangle.
+
+For example, given k = 3,
+Return [1,3,3,1].
+
+Note:
+Could you optimize your algorithm to use only O(k) extra space?
+
+## 解题思路
+
+见程序注释

Algorithms/0119.pascals-triangle-ii/pascals-triangle-ii.go

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+package Problem0119
+
+func getRow(rowIndex int) []int {
+	res := make([]int, 1, rowIndex+1)
+	res[0] = 1
+	if rowIndex == 0 {
+		return res
+	}
+
+	for i := 0; i < rowIndex; i++ {
+		res = append(res, 1)
+		for j := len(res) - 2; j > 0; j-- {
+			res[j] += res[j-1]
+		}
+	}
+
+	return res
+}

Algorithms/0119.pascals-triangle-ii/pascals-triangle-ii_test.go

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+package Problem0119
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type question struct {
+	para
+	ans
+}
+
+// para 是参数
+type para struct {
+	rowIndex int
+}
+
+// ans 是答案
+type ans struct {
+	one []int
+}
+
+func Test_Problem0119(t *testing.T) {
+	ast := assert.New(t)
+
+	qs := []question{
+
+		question{
+			para{
+				3,
+			},
+			ans{
+				[]int{1, 3, 3, 1},
+			},
+		},
+		
+		question{
+			para{
+				0,
+			},
+			ans{
+				[]int{1},
+			},
+		},
+		// 如需多个测试，可以复制上方元素。
+	}
+
+	for _, q := range qs {
+		a, p := q.ans, q.para
+		fmt.Printf("~~%v~~\n", p)
+
+		ast.Equal(a.one, getRow(p.rowIndex), "输入:%v", p)
+	}
+}