求一个javascript描述的解决方案

Question

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"

有什么javascript描述的解决方案

Answer 1

        var solveEquation = function(equation) {
                 let leftValue=0;
                let countOfLeftX = 0;
                let rightValue=0;
                let countOfRightX=0;
                let isLeft=true;
                let lastOperator='+';
                let temp='';
                for(let i=0;i<=equation.length;i++){
                    if(isLeft){
                        if(equation[i]==='+' || equation[i]==='-' || equation[i]==='='){
                            if(temp.length>0){
                                if(!!~temp.indexOf('x')){
                                    let v = temp.substring(0,temp.length-1);
                                    if(!v){
                                        v=1;
                                    }
                                    countOfLeftX = countOfLeftX +(lastOperator==='+'?+parseFloat(v):-parseFloat(v));
                                    
                                } else {
                                    leftValue = leftValue + (lastOperator==='+'?+parseFloat(temp):-parseFloat(temp));
                                }
                                temp = '';
                            } 
                            lastOperator = equation[i];

                        } else {
                            temp+=equation[i];
                        }
                        if(equation[i]==='='){
                            lastOperator='+';
                            isLeft=false;
                        }

                    } else {
                        if(equation[i]==='+' || equation[i]==='-' || i==equation.length){
                            if(temp.length>0){
                                if(!!~temp.indexOf('x')){
                                    let v = temp.substring(0,temp.length-1);
                                    if(!v){
                                        v=1;
                                    }
                                    countOfRightX = countOfRightX +(lastOperator==='+'?+parseFloat(v):-parseFloat(v));
                                    
                                } else {
                                    rightValue = rightValue + (lastOperator==='+'?+parseFloat(temp):-parseFloat(temp));
                                }
                                temp = '';
                            } 
                            if(i!==equation.length){
                                lastOperator = equation[i];
                            }
                            

                        } else {
                            temp+=equation[i];
                        }
                    }

                }
                let count = countOfLeftX - countOfRightX;
                let value = rightValue - leftValue;
                if(count ===0 && value===0){
                    return "Infinite solutions";
                } else if(count ===0 && value!==0){
                    return "No solution";
                } else {
                    return "x="+value/count;
                }
            };

Answer 2

function getX(str) {
    let left = str.split('=')[0];
    let right = str.split('=')[1];

    let arrLeft = left.match(/(\+|\-)?(\d)*(x)?/g);
    arrLeft.push(left.split(arrLeft[0])[0]);
    let arrRight = right.match(/(\+|\-)?(\d)*(x)?/g);
    arrRight.push(right.split(arrRight[0])[0]);
    
    let obj = {
        leftNumber: 0,
        leftX: 0,
        rightNumber: 0,
        rightX: 0
    };

    function getCo(el, index, side) {
        if (el === '') {
            return;
        }
        if (el.match('x')) {
            let co = null;
            co = el.match(/(\+|\-)?\d+/) || 1;
            obj[side + 'X'] += parseInt(co, 10);
        } else {
            obj[side + 'Number'] += parseInt(el, 10);
        }
    }

    arrLeft.forEach((el, index) => {
        getCo(el, index, 'left')
    });
    arrRight.forEach((el, index) => {
        getCo(el, index, 'right')
    });

    let valueNumber = obj.leftNumber - obj.rightNumber;
    let valueX = -(obj.leftX - obj.rightX);
    let outputStr = '';
    if (valueNumber === valueX) {
        outputStr = 'Infinite solutions';
    } else if (valueNumber !== 0 && valueX === 0) {
        outputStr = 'No solution';
    } else {
        outputStr = 'x=' + valueNumber / valueX;
    }
    console.log(outputStr);
}