一道题:给定一整数序列A1,A2,...,An(可能有负数),求A1到An的一个自序列,使得Ai到Aj的和最大。例如:整数序列-2,11,-4,13,-5,2,-5,-3,12,-9的最大子序列为21

给定一整数序列A1,A2,…,An(可能有负数),求A1到An的一个自序列,使得Ai到Aj的和最大。例如:整数序列-2,11,-4,13,-5,2,-5,-3,12,-9的最大子序列为21(从A2到A9)

最差的方法

```
var a = [-2,11,-4,13,-5,2,-5,-3,12,-9]
var b = new Set()

for(let n in a){
    let nm = [];
    for(let m = n;mfunction add(...nums){
    nums.reduce((x,y)=>{
        b.add(x+y);
        return x+y;
    })
}

Math.max(...b)

优化

```
var a = [-2,11,-4,13,-5,2,-5,-3,12,-9]
var b = new Set()

for(let n in a){
    a.reduce((x,y)=>{
        b.add(x+y);
        return x+y;
    })
    a.shift()
}


Math.max(...b)

ES6

```
var a = [-2,11,-4,13,-5,2,-5,-3,12,-9]
var b = new Set()

new class res{
    constructor(){
        a.reduce((x,y)=>{
            b.add(x+y);
            return x+y;
        })
        a.shift()
        if(a.length) new res()
    }
}


Math.max(...b)

最优-动态规划

var a = [-2,11,-4,13,-5,2,-5,-3,12,-9]
function method(data){
    var max = 0;
    var m = data.length;
    var sum = 0;
    for(var i=0;imax){
            max=sum;
        }else if(sum<0){
            sum = 0;
        }
    }
    return max;
}

method(a)

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