Submitted the answer of the problem-1

input.csv

@@ -1,4 +1,7 @@
-D1,150,T1
-D2,325,T2
-D3,510,T1
-D4,700,T2
+delivery_id,size,theatre_id
+D1,100,T1
+D2,300,T1
+D3,350,T1
+D1, 70, T1
+D2, 300, T1
+D1, 70, T3

main.go

@@ -0,0 +1,199 @@
+package main
+
+import (
+	"encoding/csv"
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+)
+
+type EssentialData struct {
+	TheatreID string
+	SizeSlab  string
+	MinCost   int
+	CostPerGB int
+	PartnerID string
+}
+type InputDetails struct {
+	DeliveryID string
+	Size       int
+	TheatreID  string
+}
+
+func main() {
+	mydir, err := os.Getwd()
+	if err != nil {
+		log.Println(err)
+	}
+	database, err := ParseDatabase(fmt.Sprintf("%s/%s", mydir, "pretty.csv"))
+	if err != nil {
+		log.Printf("error reading csv file %w", err)
+		return
+	}
+	inputData, err := ReadInputData(fmt.Sprintf("%s/%s", mydir, "input.csv"))
+	if err != nil {
+		log.Printf("error reading input csv file %w", err)
+		return
+	}
+	result := FindValidPartner(database, inputData)
+	WriteOutput(result)
+}
+
+func WriteOutput(output [][]string) {
+	csvFile, err := os.Create("output.csv")
+
+	if err != nil {
+		log.Fatalf("failed creating file: %s", err)
+	}
+
+	csvwriter := csv.NewWriter(csvFile)
+
+	for _, empRow := range output {
+		_ = csvwriter.Write(empRow)
+	}
+	csvwriter.Flush()
+	csvFile.Close()
+}
+
+// FindValidPartner :- function to generate effective partners of corrsponding theaters
+func FindValidPartner(database []EssentialData, inputData []InputDetails) (outputList [][]string) {
+	outputList = append(outputList, []string{"delivery_id", "delivery_possible", "cost_of_delivery", "partner_id"})
+	for _, input := range inputData {
+		var (
+			validCost int
+		)
+
+		activeIndex := -1
+		for index, dataRow := range database {
+			sizes := strings.Split(dataRow.SizeSlab, "-")
+			low, _ := strconv.Atoi(sizes[0])
+			high, _ := strconv.Atoi(sizes[1])
+			if low <= input.Size && high >= input.Size && dataRow.TheatreID == input.TheatreID {
+				deliveryCost := input.Size * dataRow.CostPerGB
+				if validCost > deliveryCost || validCost == 0 {
+					if deliveryCost < dataRow.MinCost {
+						validCost = dataRow.MinCost
+					} else {
+						validCost = deliveryCost
+					}
+
+					activeIndex = index
+				}
+			}
+		}
+		if activeIndex != -1 {
+			outputList = append(outputList, []string{input.DeliveryID, "true", fmt.Sprintf("%d", validCost), database[activeIndex].PartnerID})
+		} else {
+			outputList = append(outputList, []string{input.DeliveryID, "false"})
+		}
+
+	}
+	return
+}
+
+// ReadDataFromInput :- read headers and conents from csv
+func ReadDataFromInput(fileName string) ([]map[string]string, error) {
+	var inputData []map[string]string
+	csvfile, err := os.Open(fileName)
+	if err != nil {
+		log.Printf("error reading csv file due to error %w", err)
+		return inputData, err
+	}
+
+	defer csvfile.Close()
+
+	reader := csv.NewReader(csvfile)
+
+	rawCSVdata, err := reader.ReadAll()
+	if err != nil {
+		log.Printf("error reading row data due to error %w", err)
+		return inputData, err
+	}
+	header := []string{}
+	for lineNum, line := range rawCSVdata {
+		if lineNum == 0 {
+			for _, title := range line {
+				header = append(header, strings.TrimSpace(title))
+			}
+		} else {
+			rowValues := map[string]string{}
+			for i, value := range line {
+				rowValues[header[i]] = value
+			}
+			inputData = append(inputData, rowValues)
+		}
+	}
+	return inputData, nil
+}
+
+// ParseDatabase :- extract the contents from csv and parse it to the variable
+func ParseDatabase(fileName string) ([]EssentialData, error) {
+	var inputData []EssentialData
+	csvfile, err := os.Open(fileName)
+	if err != nil {
+		log.Printf("error reading csv file due to error %w", err)
+		return inputData, err
+	}
+
+	defer csvfile.Close()
+
+	reader := csv.NewReader(csvfile)
+
+	rawCSVdata, err := reader.ReadAll()
+	if err != nil {
+		log.Printf("error reading row data due to error %w", err)
+		return inputData, err
+	}
+
+	for lineNum, line := range rawCSVdata {
+		if lineNum > 0 {
+			cost, _ := strconv.Atoi(line[2])
+			costPerGB, _ := strconv.Atoi(line[3])
+			rowValues := EssentialData{
+				TheatreID: line[0],
+				SizeSlab:  line[1],
+				MinCost:   cost,
+				CostPerGB: costPerGB,
+				PartnerID: line[4],
+			}
+			inputData = append(inputData, rowValues)
+		}
+	}
+	return inputData, nil
+
+}
+
+//ReadInputData :- function to read input csv file
+func ReadInputData(fileName string) ([]InputDetails, error) {
+	var inputData []InputDetails
+	csvfile, err := os.Open(fileName)
+	if err != nil {
+		log.Printf("error reading csv file due to error %w", err)
+		return inputData, err
+	}
+
+	defer csvfile.Close()
+
+	reader := csv.NewReader(csvfile)
+
+	rawCSVdata, err := reader.ReadAll()
+	if err != nil {
+		log.Printf("error reading row data due to error %w", err)
+		return inputData, err
+	}
+
+	for lineNum, line := range rawCSVdata {
+		if lineNum > 0 {
+			size, _ := strconv.Atoi(strings.TrimSpace((line[1])))
+			rowValues := InputDetails{
+				DeliveryID: strings.TrimSpace(line[0]),
+				Size:       size,
+				TheatreID:  strings.TrimSpace(line[2]),
+			}
+			inputData = append(inputData, rowValues)
+		}
+	}
+	return inputData, nil
+}

output.csv

@@ -0,0 +1,7 @@
+delivery_id,delivery_possible,cost_of_delivery,partner_id
+D1,true,2000,P1
+D2,true,4500,P1
+D3,true,5250,P1
+D1,true,1750,P2
+D2,true,4500,P1
+D1,false

pretty.csv

@@ -0,0 +1,7 @@
+theatre,size_slab,minimum_cost,cost_per_gb,partner_id
+T1,0-200,2000,20,P1
+T1,200-400,3000,15,P1
+T3,100-200,4000,30,P1
+T3,200-400,5000,25,P1
+T5,100-200,2000,30,P1
+T1,0-400,1500,25,P2