int len = accumulate(point_counts.begin(), point_counts.end(), 0);
时间: 2024-05-25 19:18:12 浏览: 15
This line of code calculates the total number of points in a collection by using the `accumulate()` function from the `<numeric>` library.
`point_counts` is assumed to be a container (such as a vector or array) that contains the number of points in each sub-collection.
The first argument to `accumulate()` is the beginning of the range of values to be accumulated (in this case, `point_counts.begin()`), and the second argument is the end of the range (in this case, `point_counts.end()`).
The third argument (0) is the initial value of the sum.
The `accumulate()` function adds up all the values in the range and returns the total sum, which is assigned to the variable `len`. Therefore, `len` represents the total number of points in all sub-collections combined.