FlippingFlipper

main.go

package main

import (
	"fmt"
	"strings"
)

func contains(slice []string, item string) bool {
	set := make(map[string]struct{}, len(slice))
	for _, s := range slice {
		set[s] = struct{}{}
	}

	_, ok := set[item]
	return ok
}

func flipStack(mixStack []string) []string {
	var newStack []string
	//fmt.Println("FlipGot: ", mixStack)
	for i := len(mixStack) - 1; i >= 0; i-- {
		if mixStack[i] == "-" {
			newStack = append(newStack, "+")
		} else if mixStack[i] == "+" {
			newStack = append(newStack, "-")
		}
	}
	//fmt.Println("FlipReturn: ", newStack)
	return newStack
}

// Merge Flipped stack back on main stack
func merge(pancakeStack []string, flipped []string) []string {
	for i := range flipped {
		pancakeStack[i] = flipped[i]
	}
	return pancakeStack
}

// Main Loop
func findSadFaces(pancakeStack []string) int {
	var count int
	for contains(pancakeStack, "-") {
		for i := len(pancakeStack) - 1; i >= 0; i-- {
			if pancakeStack[0] == "+" {
				_ = merge(pancakeStack, flipStack(pancakeStack[0:1]))
				count = count + 1
				//fmt.Printf("Flip Num: %d: %s\n", count, r)
				break
			} else if pancakeStack[i] == "-" {
				_ = merge(pancakeStack, flipStack(pancakeStack[0:i+1]))
				count = count + 1
				//fmt.Printf("Flip Num: %d: %s\n", count, r)
				break
			}
		}
	}
	return count
}

func main() {
	var input1 = "-"
	var input2 = "-+"
	var input3 = "+-"
	var input4 = "+++"
	var input5 = "--+-"
	var input6 = "-+--++"

	fmt.Printf("Input %s, Flip Count: %d\n", input1, findSadFaces(strings.Split(input1, "")))
	fmt.Printf("Input %s, Flip Count: %d\n", input2, findSadFaces(strings.Split(input2, "")))
	fmt.Printf("Input %s, Flip Count: %d\n", input3, findSadFaces(strings.Split(input3, "")))
	fmt.Printf("Input %s, Flip Count: %d\n", input4, findSadFaces(strings.Split(input4, "")))
	fmt.Printf("Input %s, Flip Count: %d\n", input5, findSadFaces(strings.Split(input5, "")))
	fmt.Printf("Input %s, Flip Count: %d\n", input6, findSadFaces(strings.Split(input6, "")))
}

Output looks like:

Input -, Flip Count: 1
Input -+, Flip Count: 1
Input +-, Flip Count: 2
Input +++, Flip Count: 0
Input --+-, Flip Count: 3
Input -+--++, Flip Count: 5