Combine AoC Repos

2015/day24/main.go

@@ -0,0 +1,142 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+var pkgWeights []int64
+
+func main() {
+	scanner := bufio.NewScanner(os.Stdin)
+	for scanner.Scan() {
+		pkgWeights = append(pkgWeights, int64(mustAtoi(strings.ToLower(scanner.Text()))))
+	}
+	// Sort the weights, in the case of our input, no need.
+	totalWeight := weighPackages(pkgWeights)
+	// For Part 1:
+	//splitWeight := totalWeight / 3
+	// For Part 2:
+	splitWeight := totalWeight / 4
+	fmt.Printf("Balanced at %d\n", splitWeight)
+	// Now find the fewest number of packages that are that weight
+	result := tryPackages([]int64{}, pkgWeights, splitWeight)
+	fmt.Println("*** RESULT ***")
+	//result = makeUnique(result)
+	lowestQE := int64(-1)
+	shortest := -1
+	for i := range result {
+		if len(result[i]) <= shortest || shortest == -1 {
+			fmt.Print(result[i])
+			fmt.Printf(" L:%d", len(result[i]))
+			fmt.Printf(" QE:%d\n", getQE(result[i]))
+			shortest = len(result[i])
+			if getQE(result[i]) < lowestQE || lowestQE == -1 {
+				lowestQE = getQE(result[i])
+			}
+		}
+	}
+	fmt.Println()
+	fmt.Printf("%d\n", lowestQE)
+}
+
+func tryPackages(pkgs []int64, rem []int64, targ int64) [][]int64 {
+	// Go through all packages in 'rem' and find the combination
+	// That results in the least total number of packages
+	var findRet [][]int64
+	fewest := -1
+	if len(pkgs) > fewest && fewest != -1 {
+		return findRet
+	}
+	for i := len(rem) - 1; i >= 0; i-- {
+		t := targ - weighPackages(pkgs)
+		if rem[i] <= t {
+			tryPkgs := append(pkgs, rem[i])
+			if weighPackages(tryPkgs) == targ {
+				//if len(tryPkgs) <= fewest || fewest == -1 {
+				findRet = append(findRet, tryPkgs)
+				//	fewest = len(tryPkgs)
+				//}
+			}
+			// Not there yet... Recurse
+			rem = rem[:i]
+			res := tryPackages(tryPkgs, rem, targ)
+			for i := range res {
+				if weighPackages(res[i]) == targ {
+					//if len(res[i]) <= fewest || fewest == -1 {
+					findRet = append(findRet, res[i])
+					//	fewest = len(res[i])
+					//}
+				}
+			}
+		}
+	}
+	return findRet
+}
+
+func getQE(pkgs []int64) int64 {
+	var totalQE int64
+	for i := range pkgs {
+		if totalQE == 0 {
+			totalQE = int64(pkgs[i])
+		} else {
+			totalQE = totalQE * int64(pkgs[i])
+		}
+	}
+	return totalQE
+}
+
+func weighPackages(pkgs []int64) int64 {
+	var totalWeight int64
+	for i := range pkgs {
+		totalWeight += pkgs[i]
+	}
+	return totalWeight
+}
+
+func makeUnique(s [][]int64) [][]int64 {
+	var ret [][]int64
+	for i := range s {
+		var found bool
+		// Check if s[i] is already in ret
+		for j := range ret {
+			if isSame(ret[j], s[i]) {
+				found = true
+				break
+			}
+		}
+		if !found {
+			ret = append(ret, s[i])
+		}
+	}
+	return ret
+}
+
+func isSame(s1 []int64, s2 []int64) bool {
+	if len(s1) != len(s2) {
+		return false
+	}
+	for i := range s1 {
+		if s1[i] != s2[i] {
+			return false
+		}
+	}
+	return true
+}
+
+func itoa(i int) string {
+	return strconv.Itoa(i)
+}
+
+func mustAtoi(s string) int {
+	var i int
+	var err error
+	if i, err = strconv.Atoi(s); err != nil {
+		fmt.Println("Tried to atoi " + s)
+		os.Exit(1)
+	}
+	return i
+}