给定两个对象数组，如何找到包含“重叠”值的所有对象（例如本例中的价格）？
例如，给定数组A和数组B，我如何找到“价格”是完全匹配（例如20,30）或包含在此重叠中的所有对象（例如20.45）？
var A = [ { "id" : 1, "price" : 50, "quantity": 2 }, { "id" : 2, "price" : 40, "quantity": 2 }, { "id" : 3, "price" : 30, "quantity": 2 }, // yes { "id" : 4, "price" : 20, "quantity": 2 } // yes ]; var B = [ { "id" : 5, "price" : 30, "quantity": 2 }, // yes { "id" : 6, "price" : 20.45, "quantity": 2 }, // yes { "id" : 7, "price" : 20, "quantity": 2 }, // yes { "id" : 8, "price" : 10, "quantity": 2 }, { "id" : 9, "price" : 5, "quantity": 2 } ]; // Goal var C = [ { "id" : 3, "price" : 30, "quantity": 2 }, // yes { "id" : 4, "price" : 20, "quantity": 2 } // yes ]; var D = [ { "id" : 5, "price" : 30, "quantity": 2 }, // yes { "id" : 6, "price" : 20.45, "quantity": 2 }, // yes { "id" : 7, "price" : 20, "quantity": 2 }, // yes ];我的目标是将它们分成各自的数组（C＆D）。 但如果最终结果需要是一个组合数组，那没关系。 我也可以做那个工作。 任何有效的东西都会让我很开心。
我尝试过Underscore的交集。 如果A＆B是包含整数而不是对象的简单数组，那么交集会找到完全匹配（例如30＆30,20和20），但它仍然不包括20.45，我也需要它。 当然，我有一个对象数组而不是简单的数组，这使得它更难一点。
Given two arrays of objects, how can I find all objects that contain an 'overlapping' value (e.g. price in this case)?
For example, given array A and array B, how can I find all objects where the "price" is either an exact match (e.g. 20, 30) or contained within this overlap (e.g. 20.45)?
var A = [ { "id" : 1, "price" : 50, "quantity": 2 }, { "id" : 2, "price" : 40, "quantity": 2 }, { "id" : 3, "price" : 30, "quantity": 2 }, // yes { "id" : 4, "price" : 20, "quantity": 2 } // yes ]; var B = [ { "id" : 5, "price" : 30, "quantity": 2 }, // yes { "id" : 6, "price" : 20.45, "quantity": 2 }, // yes { "id" : 7, "price" : 20, "quantity": 2 }, // yes { "id" : 8, "price" : 10, "quantity": 2 }, { "id" : 9, "price" : 5, "quantity": 2 } ]; // Goal var C = [ { "id" : 3, "price" : 30, "quantity": 2 }, // yes { "id" : 4, "price" : 20, "quantity": 2 } // yes ]; var D = [ { "id" : 5, "price" : 30, "quantity": 2 }, // yes { "id" : 6, "price" : 20.45, "quantity": 2 }, // yes { "id" : 7, "price" : 20, "quantity": 2 }, // yes ];My goal is to keep them separated into their own arrays (C & D). But if the end result needs to be one combined array, that's okay. I can probably make that work too. Anything that works would make me happy right now.
I've tried Underscore's intersection. If A & B were simple arrays containing integers rather than objects, then intersection would work to find the exact matches (e.g. 30 & 30, 20 & 20), but it still wouldn't include 20.45, which I need as well. And, of course, I have an array of objects instead of simple arrays, which makes it a bit harder as well.
最满意答案
似乎我们可以假设这些数组按价格排序（如果没有，请执行此操作 - 请参阅排序JavaScript对象和类似数组 ），并且A包含的价格高于B （如果不是，则需要反转逻辑）。 然后就做：
var i = A.length - 1, j = 0, overlapMin = A[i].price, overlapMax = B[j].price; while (A[i].price <= overlapMax) i--; while (B[j].price >= overlapMin) j++; var C = A.slice(i+1), // to end D = B.slice(0, j);如果你需要在一个非常庞大的集合上获得更好的性能，你也可以对边界i和j使用二进制搜索。
It seems we can assume that those arrays are sorted by price (if not, do so - see Sorting an array of JavaScript objects and similar), and that A contains higher prices than B (if not, you'd need to invert the logic). Then just do:
var i = A.length - 1, j = 0, overlapMin = A[i].price, overlapMax = B[j].price; while (A[i].price <= overlapMax) i--; while (B[j].price >= overlapMin) j++; var C = A.slice(i+1), // to end D = B.slice(0, j);If you need better performance on a really huge set, you could use binary searches for the boundaries i and j as well.
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