TapeEquilibriumCodility.js

function solution(A) {
    // write your code in JavaScript (Node.js 8.9.4)
    let leftSum =0
    let rightSum= A.reduce((acc, el)=>acc+el)
    let result =null
    for (let i=0;i<A.length-1;i++){
        leftSum+=A[i]
        rightSum-=A[i]
        let diff = Math.abs(rightSum-leftSum)
        if (result ===null ||result >diff){
            result=diff
        }
    }
    return result
}