blocks|key|1011177|text|不要在循环中使用srand，只使用一次，例如在main()的开头。而srand()正是你重置它的方式。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1011178|entityMap^0|8|5|N|6|Y|7|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|O|8|@]|D|@]|E|$]]]|G|$]]

Don't use <code>srand</code> inside the loop, use it only once, e.g. at the start of <code>main()</code>. And <code>srand()</code> is exactly how you reset this.

blocks|key|1011067|text|您每次都会得到相同的随机数，因为您在循环中设置了一个种子。尽管您使用的是time()，但它每秒只更改一次，所以如果您的循环在一秒内完成(很可能会完成)，您每次都会得到相同的种子值和相同的初始随机数。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1011068|将srand()调用移到循环之外(并且只在应用程序开始时调用一次)，您应该会得到随机的“随机”数字。|1011069|entityMap^0|10|6|0|1|7|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|P|8|@]|D|@]|E|$]]]|I|$]]

You are getting the same random number each time, because you are setting a seed inside the loop. Even though you're using <code>time()</code>, it only changes once per second, so if your loop completes in a second (which it likely will), you'll get the same seed value each time, and the same initial random number.

Move the <code>srand()</code> call outside the loop (and call it only once, at the start of your app) and you should get random "random" numbers.

blocks|key|796661|text|尝试将种子srand移到循环之外，如下所示：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|796662|srand+(+time(NULL)+);
for+(int+t=0;t<10;t%2B%2B)
{
++++int+random_x;
++++random_x+=+rand()+%25+100;
++++cout<<+"\nRandom+X+=+"<<random_x;
}+|code-block|syntax|javascript|796663|正如马克·兰瑟姆在评论中所说，只有当循环没有驻留在您多次调用的函数中时，将种子移出循环才会有帮助。|796664|entityMap^0|5|5|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|S|8|@]|D|@]|E|$]]|$1|M|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|N|$]]

Try moving the seed <code>srand</code> outside the loop like so:

<pre><code>srand ( time(NULL) );
for (int t=0;t&lt;10;t++)
{
 int random_x;
 random_x = rand() % 100;
 cout&lt;&lt; "\nRandom X = "&lt;&lt;random_x;
} 
</code></pre>

As Mark Ransom says in the comment, moving the seed outside the loop will only help if the loop is not residing in a function you are calling several times.

blocks|key|797215|text|几天来我都遇到了同样的问题。将srand()排除在循环之外是一个%2B。此外，不要将rand()+%25+100赋给任何变量。只需在循环中执行rand()+%25+100。试试这个：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|797216|++++srand+(time(NULL));
++++(int+t=0;t<10;t%2B%2B)
++++{
++++cout+<<+rand()+%25+100+<<+endl;
++++}+|code-block|syntax|javascript|797217|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I had this same problem for days. Keeping srand() out of the loop is a +. Also, dont assign rand() % 100 to any variable. Simply cout rand() % 100 in the loop. Try this:

<pre><code> srand (time(NULL));
 (int t=0;t&lt;10;t++)
 {
 cout &lt;&lt; rand() % 100 &lt;&lt; endl;
 } 
</code></pre>

blocks|key|796568|text|不要每次都对生成器进行播种。将srand调用从循环中拉出|type|unstyled|depth|inlineStyleRanges|entityRanges|data|796569|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Stop seeding the generator every time.
Pull the srand call out of the loop

blocks|key|1011284|text|将srand调用移到程序的开头。现在，两次连续调用之间的时间可能相同，因此随机数生成器将在同一地点再次启动。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1011285|entityMap^0|1|5|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

Move the <code>srand</code> call to the start of the program. As you have it now, the time might be the same between two consecutive calls, so the random number generator will start again at the same spot.

blocks|key|796755|text|您需要从for循环中提取time()的初始化。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|796756|下面是一个示例，它将在windows控制台中输出预期(ahah)随机数。|796757|#include+<iostream>
#include+<windows.h>
#include+"time.h"
int+main(int+argc,+char*argv[])
{
++++srand+(+time(NULL)+);
++++for+(int+t+=+0;+t+<+10;+t%2B%2B)
++++{
++++++++int+random_x;

++++++++random_x+=+rand()+%25+100;
++++++++std::cout+<<+"\nRandom+X+=+"+<<+random_x+<<+std::endl;
++++}
++++Sleep(50000);
++++return+0;
}|code-block|syntax|javascript|796758|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

You need to extract the initilization of time() out of the for loop.

Here is an example that will output in the windows console expected (ahah) random number.

<pre><code>#include &lt;iostream&gt;
#include &lt;windows.h&gt;
#include "time.h"
int main(int argc, char*argv[])
{
 srand ( time(NULL) );
 for (int t = 0; t &lt; 10; t++)
 {
 int random_x;

 random_x = rand() % 100;
 std::cout &lt;&lt; "\nRandom X = " &lt;&lt; random_x &lt;&lt; std::endl;
 }
 Sleep(50000);
 return 0;
}
</code></pre>

blocks|key|1011378|text|在循环的每次迭代期间，time函数可能返回相同的值。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1011379|尝试在循环之前初始化随机种子。|1011380|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

The time function probably returns the same value during each iteration of the loop.

Try initializing the random seed before the loop.

blocks|key|797261|text|/*this+code+is+written+in+Turbo+C%2B%2B
+For+Visual+Studio,+code+is+in+comment*/

int+a[10],ct=0,x=10,y=10;++++//x,y+can+be+any+value,+but+within+the+range+of+
+++++++++++++++++++++++++++++//array+declared
randomize();+++++++++++++++++//there+is+no+need+to+use+this+Visual+Studio
for(int+i=0;i<10;i%2B%2B)
{+++a[i]=random(10);+++++++++//use+a[i]=rand()%2510+for+Visual+Studio
}
cout<<"\n\n";
do
{+++ct=0;
++++for(i=0;i<x;i%2B%2B)
++++{+++for(int+j=0;j<y;j%2B%2B)
++++++++{+++if(a[i]==a[j]&&i!=j)
++++++++++++{+++a[j]=random(10);++++//use+a[i]=rand()%2510+for+Visual+Studio
++++++++++++}
++++++++++++else
++++++++++++{+++ct%2B%2B;
++++++++++++}
++++++++}
++++}
}while(!(ct==(x*y)));|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|797262|我不是C%2B%2B方面的专家，但我是在学校学到的。在过去的一年里，我一直使用这个算法在一维数组中存储不同的随机值，但在经过一些更改后，这在二维数组中也可以工作。欢迎任何关于代码的建议。|unstyled|797263|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>/*this code is written in Turbo C++
 For Visual Studio, code is in comment*/

int a[10],ct=0,x=10,y=10; //x,y can be any value, but within the range of 
 //array declared
randomize(); //there is no need to use this Visual Studio
for(int i=0;i&lt;10;i++)
{ a[i]=random(10); //use a[i]=rand()%10 for Visual Studio
}
cout&lt;&lt;"\n\n";
do
{ ct=0;
 for(i=0;i&lt;x;i++)
 { for(int j=0;j&lt;y;j++)
 { if(a[i]==a[j]&amp;&amp;i!=j)
 { a[j]=random(10); //use a[i]=rand()%10 for Visual Studio
 }
 else
 { ct++;
 }
 }
 }
}while(!(ct==(x*y)));
</code></pre>

Well I'm not a pro in C++, but learnt it in school. I am using this algo for past 1 year to store different random values in a 1D array, but this will also work in 2D array after some changes.
Any suggestions about the code are welcome.

blocks|key|1011621|text|函数rand()的工作方式是，每次调用它时，它都会生成一个随机数。在您的代码中，您只调用了它一次，并将其存储到变量random_x中。要获得所需的随机数而不是将其存储到变量中，只需像这样调用函数：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1011622|for+(int+t=0;t<10;t%2B%2B)
{
++++cout+<<+"\nRandom+X+=+"+<<+rand()+%25+100;
}|code-block|syntax|javascript|1011623|entityMap^0|2|6|1L|8|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

The way the function <code>rand()</code> works is that every time you call it, it generates a random number. In your code, you've called it once and stored it into the variable <code>random_x</code>. To get your desired random numbers instead of storing it into a variable, just call the function like this:

<pre><code>for (int t=0;t&lt;10;t++)
{
 cout &lt;&lt; "\nRandom X = " &lt;&lt; rand() % 100;
}
</code></pre>

blocks|key|1011421|text|不了解男人。在测试了不同的方法后，我找到了最适合我的方法，比如10分钟。(更改代码中的数字以获得较大或较小的随机数。)|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1011422|++++int+x;
srand+(+time(NULL)+);
x+=+rand()+%25+1000+*+rand()+%25+10000+;
cout<<x;|code-block|syntax|javascript|1011423|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Don't know men. I found the best way for me after testing different ways like 10 minutes.
 ( Change the numbers in code to get big or small random number.)

<pre><code> int x;
srand ( time(NULL) );
x = rand() % 1000 * rand() % 10000 ;
cout&lt;&lt;x;
</code></pre>

Is it possible to generate different random number, every time loop runs. For example, i have:

<pre><code>for (int t=0;t&lt;10;t++)
{
 int random_x;
 srand ( time(NULL) );
 random_x = rand() % 100;
 cout&lt;&lt;"\nRandom X = "&lt;&lt;random_x;
} 
</code></pre>

But the problem is, it generates same random number everytime. Is it possible to generate different random numbers everytime loop runs?

IS there any possibility to reset random number initiallization as well?

How to generate different random numbers in a loop in C++?

Visual Studio

是否有可能在每次循环运行时生成不同的随机数。例如，我有：for (int t=0;t<10;t++){ int random_x; srand ( time(NULL) ); random_x = rand() % 100; cout<<"\nRandom X = "<<random_x;} 但问题是，它每次都会生成相同的随机数。是否有可能在每次循环运行时生成不同的随机数？

问在C++中如何在循环中生成不同的随机数？
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