Submission #2856952

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Source Code Expand

package main

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

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	n := scanInt(sc)
	found := make(map[int]int, n)
	candidates := make([]int, 0)

	for i := 0; i < n; i++ {
		l := scanInt(sc)
		if found[l] >= 0 {
			found[l] += 1
			if found[l] == 2 || found[l] == 4 {
				candidates = append(candidates, l)
			}
			if found[l] == 4 {
				found[l] = -1
			}
		}
	}

	if len(candidates) < 2 {
		fmt.Println(0)
		return
	}

	sort.Ints(candidates)
	a := candidates[len(candidates)-1]
	b := candidates[len(candidates)-2]
	fmt.Println(a * b)
}

func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	val, _ := strconv.Atoi(sc.Text())
	return val
}

Submission Info

Judge Result