advent_of_code_2025/5/solve_1.go

package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
)

type interval struct {
	lb,ub int64
}

func main(){
	fmt.Println("Advent of Code 2025 - Day 5 - Part 1")
	f,_:= os.Open("5/input")
	defer f.Close()
	scanner := bufio.NewScanner(f)

	var ranges []interval;
	
	for scanner.Scan(){
		line := scanner.Text()
		if (len(line) == 0){
			break
		}
		line_split := strings.Split(line, "-")
		lb,_ := strconv.ParseInt(line_split[0],10,64)
		ub,_ := strconv.ParseInt(line_split[1],10,64)
		ranges = append(ranges, interval{lb,ub})
	}

	res := 0
	for scanner.Scan(){
		line := scanner.Text()
		id,_ := strconv.ParseInt(line,10,64)
		for _, itvl := range ranges {
			if (itvl.lb <= id  && id <= itvl.ub) {
				res++
				break
			}
		}
	}
	fmt.Println(res)
}