/**
640. Solve the Equation

Solve a given equation and return the value of x in the form of string "x=#value". The equation contains only '+', '-' operation, the variable x and its coefficient.

If there is no solution for the equation, return "No solution".

If there are infinite solutions for the equation, return "Infinite solutions".

If there is exactly one solution for the equation, we ensure that the value of x is an integer.

Example 1:
Input: "x+5-3+x=6+x-2"
Output: "x=2"
Example 2:
Input: "x=x"
Output: "Infinite solutions"
Example 3:
Input: "2x=x"
Output: "x=0"
Example 4:
Input: "2x+3x-6x=x+2"
Output: "x=-1"
Example 5:
Input: "x=x+2"
Output: "No solution"


testcase:
"x+5-3+x=6+x-2"
"-x=-1"
"x=x"
"2x=x"
"2x+3x-6x=x+2"
"x=x+2"
"2-x+x+3x=2x-x+x+3"
**/

import (
    "strings"
    "strconv"
)
func solveEquation(equation string) string {
    var res [][]int = [][]int{{0,0},{0,0}}
    for i,s := range strings.Split(equation, "=") {
        res[i][0], res[i][1] = coefficient(s)
    }

    l := res[0][0] - res[1][0]
    r := res[0][1] - res[1][1]
    r *= -1

    if l ==0 && r == 0 {
        return "Infinite solutions"
    } else if l == 0 {
        return "No solution"
    } else if r == 0 {
        return "x=0"
    } else {
        return "x="+strconv.Itoa(r/l)
    }
}

func coefficient(s string) (int, int) {
    co, val := 0, 0
    out := ""
    for _, c := range s {
        if strings.ContainsAny(string(c), "+-") {
            if len(out)>0 {
                _co, _val := conv(out)
                co += _co
                val += _val
                out = ""
            }
            if c == '+' {
                continue
            }
        }
        out += string(c)
    }
    _co, _val := conv(out)
    co += _co
    val += _val
    return co, val
}

func conv(s string) (int,int) {
    co, val := 0, 0

    if strings.ContainsRune(s, 'x') {
        if s == "x" {
            co = 1
        } else if s == "-x" {
            co = -1
        } else {
            fmt.Println(s[:len(s)-1])
            co,_ = strconv.Atoi(s[:len(s)-1])
        }
    } else {
        val,_ = strconv.Atoi(s)
    }
    return co, val
}