Add solution 0554

leetcode/0554.Brick-Wall/554. Brick Wall.go

@@ -0,0 +1,19 @@
+package leetcode
+
+func leastBricks(wall [][]int) int {
+	m := make(map[int]int)
+	for _, row := range wall {
+		sum := 0
+		for i := 0; i < len(row)-1; i++ {
+			sum += row[i]
+			m[sum]++
+		}
+	}
+	max := 0
+	for _, v := range m {
+		if v > max {
+			max = v
+		}
+	}
+	return len(wall) - max
+}

leetcode/0554.Brick-Wall/554. Brick Wall_test.go

@@ -0,0 +1,57 @@
+package leetcode
+
+import (
+	"fmt"
+	"testing"
+)
+
+type question554 struct {
+	para554
+	ans554
+}
+
+// para 是参数
+// one 代表第一个参数
+type para554 struct {
+	wall [][]int
+}
+
+// ans 是答案
+// one 代表第一个答案
+type ans554 struct {
+	one int
+}
+
+func Test_Problem554(t *testing.T) {
+
+	qs := []question554{
+
+		{
+			para554{[][]int{{1, 2, 2, 1}, {3, 1, 2}, {1, 3, 2}, {2, 4}, {3, 1, 2}, {1, 3, 1, 1}}},
+			ans554{2},
+		},
+
+		{
+			para554{[][]int{{1}, {1}, {1}}},
+			ans554{3},
+		},
+
+		{
+			para554{[][]int{{1, 1, 0}, {1, 1, 0}, {0, 0, 1}}},
+			ans554{1},
+		},
+
+		{
+			para554{[][]int{{1, 1, 0}, {1, 1, 1}, {0, 1, 1}}},
+			ans554{0},
+		},
+	}
+
+	fmt.Printf("------------------------Leetcode Problem 554------------------------\n")
+
+	for _, q := range qs {
+		_, p := q.ans554, q.para554
+		fmt.Printf("【input】:%v       【output】:%v\n", p, leastBricks(p.wall))
+	}
+	fmt.Printf("\n\n\n")
+}

leetcode/0554.Brick-Wall/README.md

@@ -0,0 +1,68 @@
+# [554. Brick Wall](https://leetcode.com/problems/brick-wall/)
+
+## 题目
+
+There is a rectangular brick wall in front of you with `n` rows of bricks. The `ith` row has some number of bricks each of the same height (i.e., one unit) but they can be of different widths. The total width of each row is the same.
+
+Draw a vertical line from the top to the bottom and cross the least bricks. If your line goes through the edge of a brick, then the brick is not considered as crossed. You cannot draw a line just along one of the two vertical edges of the wall, in which case the line will obviously cross no bricks.
+
+Given the 2D array `wall` that contains the information about the wall, return *the minimum number of crossed bricks after drawing such a vertical line*.
+
+**Example 1:**
+
+![https://assets.leetcode.com/uploads/2021/04/24/cutwall-grid.jpg](https://assets.leetcode.com/uploads/2021/04/24/cutwall-grid.jpg)
+
+```
+Input: wall = [[1,2,2,1],[3,1,2],[1,3,2],[2,4],[3,1,2],[1,3,1,1]]
+Output: 2
+
+```
+
+**Example 2:**
+
+```
+Input: wall = [[1],[1],[1]]
+Output: 3
+
+```
+
+**Constraints:**
+
+- `n == wall.length`
+- `1 <= n <= 10^4`
+- `1 <= wall[i].length <= 10^4`
+- `1 <= sum(wall[i].length) <= 2 * 10^4`
+- `sum(wall[i])` is the same for each row `i`.
+- `1 <= wall[i][j] <= 2^31 - 1`
+
+## 题目大意
+
+你的面前有一堵矩形的、由 n 行砖块组成的砖墙。这些砖块高度相同（也就是一个单位高）但是宽度不同。每一行砖块的宽度之和应该相等。你现在要画一条 自顶向下 的、穿过 最少 砖块的垂线。如果你画的线只是从砖块的边缘经过，就不算穿过这块砖。你不能沿着墙的两个垂直边缘之一画线，这样显然是没有穿过一块砖的。给你一个二维数组 wall ，该数组包含这堵墙的相关信息。其中，wall[i] 是一个代表从左至右每块砖的宽度的数组。你需要找出怎样画才能使这条线 穿过的砖块数量最少 ，并且返回 穿过的砖块数量 。
+
+## 解题思路
+
+- 既然穿过砖块中缝不算穿过砖块，那么穿过最少砖块数量一定是穿过很多中缝。按行遍历每一行的砖块，累加每行砖块宽度，将每行砖块“缝”的坐标存在 map 中。最后取出 map 中出现频次最高的缝，即为铅垂线要穿过的地方。墙高减去缝出现的频次，剩下的即为穿过砖块的数量。
+
+## 代码
+
+```go
+package leetcode
+
+func leastBricks(wall [][]int) int {
+	m := make(map[int]int)
+	for _, row := range wall {
+		sum := 0
+		for i := 0; i < len(row)-1; i++ {
+			sum += row[i]
+			m[sum]++
+		}
+	}
+	max := 0
+	for _, v := range m {
+		if v > max {
+			max = v
+		}
+	}
+	return len(wall) - max
+}
+```