Module1, module2, module3, module4 and module5 solutions + tests

golang/go.mod

@@ -1,5 +1,11 @@
 module isuct.ru/informatics2022
 
-go 1.16
+go 1.19
 
-require github.com/stretchr/testify v1.8.1 // indirect
+require github.com/stretchr/testify v1.8.1
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

golang/go.sum

@@ -5,12 +5,12 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
-github.com/stretchr/objx v0.5.0 h1:1zr/of2m5FGMsad5YfcqgdqdWrIhu+EBEJRhR1U7z/c=
 github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=

golang/internal/module1/hello.go

@@ -0,0 +1,20 @@
+package module1
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strings"
+)
+
+func SayHello() {
+	reader := bufio.NewReader(os.Stdin)
+	line, err := reader.ReadString('\n')
+	if err != nil {
+		panic(err)
+	}
+
+	line = strings.TrimSuffix(line, "\n")
+	line = strings.TrimSuffix(line, "\r")
+	fmt.Printf("Hello, %s!", line)
+}

golang/internal/module2/task1.go

@@ -0,0 +1,50 @@
+package module2
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"reflect"
+)
+
+func printSlice(slice []int, length int, writer io.Writer) {
+	i := 0
+	for ; i < length-1; i++ {
+		fmt.Fprintf(writer, "%d ", slice[i])
+	}
+	fmt.Fprintf(writer, "%d\n", slice[i])
+}
+
+func bubbleSort(numbers []int, length int) (hasChanged bool) {
+	swapper := reflect.Swapper(numbers)
+	writer := bufio.NewWriter(os.Stdout)
+
+	for i := 0; i < length-1; i++ {
+		for j := 0; j < length-1-i; j++ {
+			if numbers[j] > numbers[j+1] {
+				swapper(j, j+1)
+				hasChanged = true
+				printSlice(numbers, length, writer)
+			}
+		}
+		writer.Flush()
+	}
+	return hasChanged
+}
+
+func SolutionBubbleSort() {
+	n := 0
+	reader := bufio.NewReader(os.Stdin)
+	fmt.Fscanln(reader, &n)
+
+	numbers := make([]int, n)
+	for i := 0; i < n; i++ {
+		fmt.Fscanf(reader, "%d", &numbers[i])
+	}
+
+	hasChanged := bubbleSort(numbers, n)
+	if !hasChanged {
+		fmt.Print(0)
+	}
+}

golang/internal/module2/task2.go

@@ -0,0 +1,60 @@
+package module2
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+	"reflect"
+)
+
+const idIndex = 0
+const priceIndex = 1
+
+func swapColumns(listOfItems [][]int, indexSortedElem, indexKeyElem int) {
+	swapper := reflect.Swapper(listOfItems)
+	if (listOfItems[indexSortedElem][priceIndex] == listOfItems[indexKeyElem][priceIndex]) &&
+		(listOfItems[indexKeyElem][idIndex] < listOfItems[indexSortedElem][idIndex]) {
+		swapper(indexKeyElem, indexSortedElem)
+	} else if listOfItems[indexKeyElem][priceIndex] > listOfItems[indexSortedElem][priceIndex] {
+		swapper(indexKeyElem, indexSortedElem)
+	}
+}
+
+func insertionSort(listOfItems [][]int, length int) {
+	for i := 1; i < length; i++ {
+		for j := i; j > 0; j-- {
+			if listOfItems[j][priceIndex] < listOfItems[j-1][priceIndex] {
+				break
+			} else {
+				swapColumns(listOfItems, j-1, j)
+			}
+		}
+	}
+}
+
+func printListOfItems(listOfItems [][]int, length int) {
+	writer := bufio.NewWriter(os.Stdout)
+	for i := 0; i < length; i++ {
+		_, err := fmt.Fprintf(writer, "%d %d\n", listOfItems[i][idIndex], listOfItems[i][priceIndex])
+		if err != nil {
+			log.Fatal(err)
+		}
+	}
+	writer.Flush()
+}
+
+func SolutionInsertionSort() {
+	reader := bufio.NewReader(os.Stdin)
+	n := 0
+	fmt.Fscanln(reader, &n)
+
+	listOfItems := make([][]int, n)
+	for i := 0; i < n; i++ {
+		listOfItems[i] = make([]int, 2)
+		fmt.Fscanf(reader, "%d %d\n", &listOfItems[i][idIndex], &listOfItems[i][priceIndex])
+	}
+
+	insertionSort(listOfItems, n)
+	printListOfItems(listOfItems, n)
+}

golang/internal/module2/task3.go

@@ -0,0 +1,78 @@
+package module2
+
+import (
+	"bufio"
+	"fmt"
+	"math"
+	"os"
+)
+
+func merge(numbers []int, startIndex, middleIndex, endIndex int) {
+	quantityOfElemsOnLeft := middleIndex - startIndex
+	quantityOfElemsOnRight := endIndex - middleIndex + 1
+
+	left := make([]int, quantityOfElemsOnLeft+1)
+	right := make([]int, quantityOfElemsOnRight+1)
+
+	left[quantityOfElemsOnLeft] = math.MaxInt
+	right[quantityOfElemsOnRight] = math.MaxInt
+
+	for i := 0; i < quantityOfElemsOnLeft; i++ {
+		left[i] = numbers[startIndex+i]
+	}
+
+	for j := 0; j < quantityOfElemsOnRight; j++ {
+		right[j] = numbers[middleIndex+j]
+	}
+
+	i, j := 0, 0
+	k := startIndex
+	for ; k <= endIndex; k++ {
+		if left[i] <= right[j] {
+			numbers[k] = left[i]
+			i++
+		} else {
+			numbers[k] = right[j]
+			j++
+		}
+	}
+
+	fmt.Printf("%d %d %d %d\n", startIndex+1, endIndex+1, numbers[startIndex], numbers[endIndex])
+}
+
+func mergeSort(numbers []int, startIndex, endIndex int) {
+	if endIndex > startIndex {
+		/*
+			Пришлось включить серединный элемент в правую часть, а не в левую,
+			чтобы ответы на задачу совпадали с яндекс контестом
+		*/
+		middleIndex := (startIndex+endIndex)/2 + (startIndex+endIndex)%2
+		mergeSort(numbers, startIndex, middleIndex-1)
+		mergeSort(numbers, middleIndex, endIndex)
+		merge(numbers, startIndex, middleIndex, endIndex)
+	}
+}
+
+func printSortedSliceMergeSort(numbers []int, length int) {
+	writer := bufio.NewWriter(os.Stdout)
+	i := 0
+	for ; i < length-1; i++ {
+		fmt.Fprintf(writer, "%d ", numbers[i])
+	}
+	fmt.Fprintf(writer, "%d", numbers[i])
+	writer.Flush()
+}
+
+func SolutionMergeSort() {
+	reader := bufio.NewReader(os.Stdin)
+	n := 0
+	fmt.Fscanln(reader, &n)
+
+	numbers := make([]int, n)
+	for i := 0; i < n; i++ {
+		fmt.Fscanf(reader, "%d", &numbers[i])
+	}
+
+	mergeSort(numbers, 0, n-1)
+	printSortedSliceMergeSort(numbers, n)
+}

golang/internal/module2/task4.go

@@ -0,0 +1,66 @@
+package module2
+
+import (
+	"bufio"
+	"fmt"
+	"math"
+	"os"
+)
+
+func mergeInvCount(numbers []int, startIndex, middleIndex, endIndex int) (invCount int64) {
+	quantityOfElemsOnLeft := middleIndex - startIndex + 1
+	quantityOfElemsOnRight := endIndex - middleIndex
+
+	left := make([]int, quantityOfElemsOnLeft+1)
+	right := make([]int, quantityOfElemsOnRight+1)
+
+	left[quantityOfElemsOnLeft] = math.MaxInt
+	right[quantityOfElemsOnRight] = math.MaxInt
+
+	for i := 0; i < quantityOfElemsOnLeft; i++ {
+		left[i] = numbers[startIndex+i]
+	}
+
+	for j := 0; j < quantityOfElemsOnRight; j++ {
+		right[j] = numbers[middleIndex+1+j]
+	}
+
+	i, j := 0, 0
+	k := startIndex
+	for ; k <= endIndex; k++ {
+		if left[i] <= right[j] {
+			numbers[k] = left[i]
+			i++
+		} else {
+			numbers[k] = right[j]
+			invCount += int64(middleIndex) - int64(startIndex) - int64(i) + 1
+			j++
+		}
+	}
+
+	return invCount
+}
+
+func mergeSortInvCount(numbers []int, startIndex, endIndex int) (invCount int64) {
+	if endIndex > startIndex {
+		middleIndex := (startIndex + endIndex) / 2
+		invCount = mergeSortInvCount(numbers, startIndex, middleIndex)
+		invCount += mergeSortInvCount(numbers, middleIndex+1, endIndex)
+		invCount += mergeInvCount(numbers, startIndex, middleIndex, endIndex)
+	}
+	return invCount
+}
+
+func SolutionInversionCount() {
+	reader := bufio.NewReader(os.Stdin)
+	n := 0
+	fmt.Fscanln(reader, &n)
+
+	numbers := make([]int, n)
+	for i := 0; i < n; i++ {
+		fmt.Fscanf(reader, "%d", &numbers[i])
+	}
+
+	invCount := mergeSortInvCount(numbers, 0, n-1)
+	fmt.Print(invCount)
+}