public member function （公共成員函式）
<random>
| (1) | void seed(); |
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| (2) | void seed (result_type val); |
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| (3) | template <class Sseq>void seed (Sseq& q); |
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Seed base engine （為基礎引擎設定種子）
Re-initializes the state of the base engine, by calling its （透過呼叫 基礎 引擎的）seed （種子）member function with the same argument (if any). （同名引數（如果存在）成員函式，重新初始化其狀態。）
引數
- val （val）
- A seeding value. This value is passed to the base engine's constructor. （一個種子值。此值會被傳遞給 基礎 引擎的建構函式。）
result_type （結果型別）is a member type, defined as an alias of the type of elements produced by base. （是一個成員型別，定義為 基礎 引擎產生的元素型別的別名。）
- q （q）
- 一個種子序列物件，例如seed_seq型別的物件。
Sseq （Sseq）應為具有generate成員函式的種子序列類。
示例
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// shuffle_order_engine::seed example
#include <iostream>
#include <chrono>
#include <random>
int main ()
{
typedef std::chrono::high_resolution_clock myclock;
myclock::time_point beginning = myclock::now();
// obtain a seed from a user string:
std::string str;
std::cout << "Please, enter a seed: ";
std::getline(std::cin,str);
std::seed_seq seed1 (str.begin(),str.end());
// obtain a seed from the timer
myclock::duration d = myclock::now() - beginning;
unsigned seed2 = d.count();
// knuth_b is a standard shuffle_order_engine type:
std::knuth_b generator (seed1);
std::cout << "Your seed produced: " << generator() << std::endl;
generator.seed (seed2);
std::cout << "A time seed produced: " << generator() << std::endl;
return 0;
}
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可能的輸出
Please, enter a seed: Knuth
Your seed produced: 361757427
A time seed produced: 1437485371
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複雜度
Determined by the base engine. （由 基礎 引擎決定。）