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parallel_for_each形式为:

Concurrency::parallel_for_each(start_iterator, end_iterator, function_object);

parallel_for也是类似的形式:

Concurrency::parallel_for(start_value, end_value, function_object);

那么多核编程中使用的算法Concurrency::parallel_for和算法有什么区别?Concurrency::parallel_for_each

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1 回答 1

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我不知道你在说什么库,但看起来这个库需要迭代器:

Concurrency::parallel_for_each(start_iterator, end_iterator, function_object);

并且可能具有与此相同的效果(尽管不一定以相同的顺序):

for(sometype i = start_iterator; i != end_iterator; ++i) {
    function_object(*i);
}

例如:

void do_stuff(int x) { /* ... */ }
vector<int> things;
// presumably calls do_stuff() for each thing in things
Concurrency::parallel_for_each(things.begin(), things.end(), do_stuff);

另一个取值,因此很可能与此具有类似的效果(但同样,没有保证顺序):

for(sometype i = start_value; i != end_value; ++i) {
    function_object(i);
}

尝试运行这个:

void print_value(int value) {
    cout << value << endl;
}

int main() {
    // My guess is that this will print 0 ... 9 (not necessarily in order)
    Concurrency::parallel_for(0, 10, print_value);
    return 0;
}

编辑:您可以在Parallel Algorithm references中找到这些行为的确认。

于 2011-12-14T03:45:04.620 回答