Add Go

Author: chuanchan1116

.travis.yml

@@ -3,6 +3,8 @@ language: crystal
 before_install:
   - sudo apt-get -qq update
   - sudo apt-get install -y default-jdk haskell-platform mono-mcs
+  - gimme 1.9.2
+  - go version
 
 install: make clean build
 

Makefile

@@ -16,6 +16,7 @@ build:
 	javac -d $(BIN_DIR) Main.java
 	ghc -O2 main.hs -outputdir=$(BUILD_DIR) -o $(BIN_DIR)/haskell
 	mcs main.cs -out:bin/csharp -optimize+
+	go build -o $(BIN_DIR)/go main.go
 
 test:
 	mkdir $(TMP_DIR)
@@ -35,4 +36,6 @@ test:
 	@cmp $(TMP_DIR)/crystal.out $(TMP_DIR)/python3.out || (echo "Failed: Python3" && exit 1)
 	bin/csharp < tmp/test_data.in > tmp/csharp.out
 	@cmp $(TMP_DIR)/crystal.out $(TMP_DIR)/csharp.out || (echo "Failed: C#" && exit 1)
+	$(BIN_DIR)/go < $(TMP_DIR)/test_data.in > $(TMP_DIR)/go.out
+	@cmp $(TMP_DIR)/crystal.out $(TMP_DIR)/go.out || (echo "Failed: Go" && exit 1)
 	@echo "Passed"

README.md

@@ -14,6 +14,7 @@ Solve 2D Rank Finding Problem in Several Languages
 - Haskell
 - Python 3
 - C#
+- Go
 
 ## Problem
 
@@ -80,5 +81,5 @@ Your output should consist of a single line for each test case containing n numb
 - [c910335](https://github.com/c910335) Tatsujin Chin - creator, maintainer
 - [scps940707](https://github.com/scps940707) YyWang - Java
 - [sifmelcara](https://github.com/sifmelcara) mingchuan - Haskell
-- [chuanchan1116](https://github.com/chuanchan1116) William Tsai - Python 3
+- [chuanchan1116](https://github.com/chuanchan1116) William Tsai - Python 3, Go
 - [sharknevercries](https://github.com/sharknevercries) ZhengYuan Lee - C#

main.go

@@ -0,0 +1,87 @@
+package main
+
+import(
+    "fmt"
+    "bufio"
+    "os"
+    "strconv"
+    "sort"
+)
+
+
+type Point struct {
+    i, x, y int
+}
+
+var rank []int
+
+func findRank(p []Point) []Point{
+    if len(p) <= 1 {
+        return p
+    }
+    var ret []Point
+    i, li, ri := 0, 0, 0
+    l := findRank(p[:int(len(p)/2)])
+    r := findRank(p[int(len(p)/2):])
+    ret = make([]Point, len(p))
+    for {
+        if l[li].y <= r[ri].y {
+            ret[i] = l[li]
+            li++
+            if li >= len(l) {
+                for _, v := range r[ri:] {
+                    rank[v.i] += li
+                    ret[i+1] = v
+                    i++
+                }
+                break
+            }
+        } else {
+            ret[i] = r[ri]
+            rank[r[ri].i] += li
+            ri++
+            if ri >= len(r) {
+                copy(ret[i+1:], l[li:])
+                break
+            }
+        }
+        i++
+    }
+    copy(p, ret)
+    return p
+}
+
+func main() {
+    scanner := bufio.NewScanner(os.Stdin)
+    scanner.Split(bufio.ScanWords)
+    out := bufio.NewWriter(os.Stdout)
+    defer out.Flush()
+    for scanner.Scan() {
+        n, _ := strconv.Atoi(scanner.Text())
+        if n == 0 {
+            break
+        }
+        var point []Point
+        rank = make([]int, n)
+        for i := 0; i < n; i++ {
+            scanner.Scan()
+            x, _ := strconv.Atoi(scanner.Text())
+            scanner.Scan()
+            y, _ := strconv.Atoi(scanner.Text())
+            point = append(point, Point{i, x, y})
+        }
+        sort.Slice(point, func(i, j int) bool {
+            if point[i].x != point[j].x {
+                return point[i].x < point[j].x
+            } else {
+                return point[i].y < point[j].y
+            }
+        })
+        findRank(point)
+        fmt.Fprintf(out, "%d",rank[0])
+        for i := 1; i < len(rank); i++ {
+            fmt.Fprintf(out, " %d", rank[i])
+        }
+        fmt.Fprintf(out, "\n")
+    }
+}