1465. Order Of Tasks 这题目什么意思？

[b]
[/b][b]
[/b]LintCode上的这道题目题意是什么，大家有看懂吗？


1465. Order Of Tasks
[color=rgba(0, 0, 0, 0.65098)]

[b]Description[/b]
[color=rgba(0, 0, 0, 0.65098)]

There are n different tasks, the execution time of tasks are t[], and the probability of success are p[]. When a task is completed or all tasks fail, the operation ends. Tasks are performed in a different order, and it is expected that the time to stop the action is generally different. Please answer in what order to perform the task in order to make the end of the expected action the shortest time? If the expected end time of the two task sequences is the same, the lexicographic minimum order of tasks is returned.

[color=rgba(0, 0, 0, 0.65098)]

• 1≤n≤50,1≤ti≤10,0≤pi≤11≤n≤50,1≤ti≤10,0≤pi≤1
• nn is a positive integer, titi is a positive integer, pipi is a floating-point number
  

[color=rgba(0, 0, 0, 0.65098)]Have you met this question in a real interview?  Yes
[color=rgba(0, 0, 0, 0.65098)][b]Example[/b]

Given n=1, t=[1], p=[1.0], return [1].

Explanation:The shortest expected action end time is 1.0*1+(1.0-1.0)*1=1.0

Given n=2, t=[1,2], p=[0.3, 0.7], return [2,1].

Explanation:The shortest expected action end time is 0.7*2+(1.0-0.7)*0.3*(2+1)+(1.0-0.7)*(1.0-0.3)*(2+1)=2.3

贴一个提交的代码：


class Solution {public:    /**     * @param n: The number of tasks     * @param t: The time array t     * @param p: The probability array p     * @return: Return the order     */    struct node    {        int id, t;        double p;        node()        {}        node(int id, int t, double p) : id(id), t(t), p(p)        {}    };    static bool comp(node &l, node &r)    {        return l.p * r.t > r.p * l.t || abs(l.p * r.t - r.p * l.t) < 1e-4 && l.id < r.id;    }    vector<int> getOrder(int n, vector<int> &t, vector<double> &p) {        // Write your code here        vector<node> a(n);        for(int i = 0; i < n; i++)            a[i] = node(i + 1, t[i], p[i]);        sort(a.begin(), a.end(), comp);        vector<int> res;        for(auto &it: a)            res.push_back(it.id);        return res;    }};

吴亦几 发表于 2018-8-19 08:11
这题昨天lintcde测试了， 我有点后悔当时看了这个帖没细想。skrrrrrrr

我题也是看了才明白的， 他意思是 ...

这么一说那就明白了，多谢啦。