题目：TapeEquilibrium

思路：

• 细心观察会发现，其实每次两个值的差delta就是上一个差减去2倍的下一个数
• 举个路子说明，比如数组A=[3, 1, 2, 4, 3]，第一个差值是|3-10|=7，第二个差值是|4-9|=5，其实 5=7-2*A[1]，那么下一个差值就是 |5-2*A[2]|=1
• 注意耗时就行

解答：

js scilab">js-function">js-keyword">function js-title">solutionjs-params">(A) {
    var js-built_in">sum = js-transposed_variable">A.reduce(js-function">js-keyword">functionjs-params">(a,b){js-title">return js-title">a+js-title">b})
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    js-keyword">for(var p = js-number">0 ; p < js-transposed_variable">A.js-built_in">length-js-number">1;p++){
        js-built_in">sum -= js-number">2*Ajs-matrix">[p]
        var delta = js-transposed_variable">Math.js-built_in">abs(js-built_in">sum)
        js-keyword">if(delta < js-built_in">min){
            js-built_in">min = delta
        }
    }
    js-keyword">return js-built_in">min
}