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C Programming; Producing a 2-Dimensional Matrix with Random Numbers without Repetition

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问题 I'd like to produce a 6x6 matrix by inserting random numbers to the elements in the row and column without repeating. This is my code so far. Thank you for your help! #include <stdio.h> #include <stdlib.h> int main(void) { int array[6][6]; int rows, columns; int random; srand((unsigned)time(NULL)); for(rows=0;rows<6;rows++) { for(columns=0;columns<6;columns++) { random=rand()%36+1; array[rows][columns] = random; printf("%i",array[rows][columns]); } printf("\n"); } return 0; } 回答1: To avoid

[leetcode 6] copy-list-with-random-pointer

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题目描述现在有一个这样的链表：链表的每一个节点都附加了一个随机指针，随机指针可能指向链表中的任意一个节点或者指向空。请对这个链表进行深拷贝。 A linked list is given such that each node contains an additional random pointer which could point to any node in the list or null. Return a deep copy of the list. 思路为原链表每个结点编号，并创建一个 <RandomListNode *, int> 的map的key-value对作为目录；按照编号个数创建新链表，并为新链表创建一个<int，RandomListNode *> 的查找目录；遍历原链表完成深拷贝。最先按照这个思路做时新链表没有用new的方式创建而是直接创建结点对象，导致函数运行完后局部变量在栈中被释放，答案出错。后来改用new在堆内存申请空间，运行成功。运行时间：25 ms，占用内存：1772K 代码 /** * Definition for singly-linked list with a random pointer. * struct RandomListNode { * int label; * RandomListNode *next,

Canvas Image Shuffle

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问题 So I have a Canvas and a set of 18 Images in it and I want to shuffle the Images foreach (var myImg in GameCanvas.Children.OfType<Image>()) { GetTop.Add(Canvas.GetTop(myImg)); GetLeft.Add(Canvas.GetLeft(myImg)); listNum++; myImg.IsTapEnabled = false; } I have this part to add the Top and Left of each image in a separate list BUT when I try this foreach (var myImg in GameCanvas.Children.OfType<Image>()) { int ran = rand.Next(GetTop.Count); double Top = GetTop[ran]; double Left = GetLeft[ran];

Is there a way to guess the next number java random? [duplicate]

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问题 This question already has answers here : Difference between java.util.Random and java.security.SecureRandom (7 answers) Closed 3 years ago . Question is in the title, quite new here so don't know much about the site yet. Want to use hash for creating "more randomness" but not yet sure about Java's Math.Random() yet, is it possible to crack it? 回答1: If you are using java.util.Random() , it is possible. Have a look at this Code For better security, you have to use SecureRandom as below

Make my circles randomly disappear and after random seconds again appear

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问题 So I'm making very simple game. Game is about some guy who jumps on rocks(circles) and rocks sometimes get covered by water and when they are, you cant stand on them otherwise you'll fall into water and drown. I'm stuck in part where i need to make those rocks disappear(be covered by water). So I need at randomized time make them disappear, for random seconds(not too long) make them "invisible" and then again they need to show up. I'm still kinda beginner and I would appreciate any kind of

Trying to take 1 random digit at a time

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问题 I am new to cpp programing, and new to stackoverflow. I have a simple situation and a problem that is taking more time than reasonable to solve, so I thought I'd ask it here. I want to take one digit from a rand() at a time. I have managed to strip of the digit, but I can't convert it to an int which I need because it's used as an array index. Can anyone help? I'd be appreciative. Also if anyone has a good solution to get evenly-distributed-in-base-10 random numbers, I'd like that too... of

Trying to take 1 random digit at a time

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Using multiple colors in matrix batch file

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问题 I've been messing around with batch files a bit, and have this code running. I did not write it, I found it, and it just runs random blue numbers in command prompt until you exit. My question is this, I want to make one where every character is a random color. so essentially, it'll look like a rainbow vomited skittles on my screen. But i digress. That is my challenge, and so far i have failed at solving it. Any ideas would be great! @echo off color 01 cls :a set /a a=%random% if %a% geq 16384

SAS Change the Proportion of a Random Sample

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问题 Is there a way to change and manipulate the proportion of a variable in SAS in random sampling? Lets say that I have table consisting 1000 people. (500 male and 500 female) If I want to have a random sample of 100 with gender strata - I will have 50 males and 50 females in my output. I want to learn if there is a way to have the desired proportion of gender values? Can ı have a random sample of 100 with 70 males and 30 females ? 回答1: PROC SURVEYSELECT is the way to do this, using a dataset

How to implement a function of a random variable in PyMC which could be sampled by MCMC Metropolis?

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问题 If you have a random variable $X$ and a function $f$, you can define $y=f(X)$ as a new random variable with a probability density function as follows: $p(y)=(f^{-1})'(y)p(x)$. For details see here. Now I have defined a random variable alpha, with an exponential distribution in the following code. I want to add to my model, log(alpha) as a new random variable. How should I implement it in my model? I already made an effort but it seems that it is wrong, and the reason as been pointed out in