{"ScriptPreparationCode":"var users = {}\r\n\r\nfor (var i = 0; i \u003C 1000; i\u002B\u002B) {\r\n if (i % 2) {\r\n \tusers[i] = {a: \u0022a\u0022, b: \u0022b\u0022}\r\n } else {\r\n \tusers[i] = {b: \u0022b\u0022}\r\n } \r\n}","TestCases":[{"Name":"Lodash reduce","Code":" var res = _.chain(users)\r\n .reduce((acc, a, userID) =\u003E {\r\n if (a === \u0022a\u0022) {\r\n acc.push(userID)\r\n }\r\n return acc\r\n }, [])\r\n .value()","IsDeferred":false},{"Name":"Native reduce","Code":"var res = []\r\n\r\nfor (key in users) {\r\n if (users[key].a) res.push(key) \r\n}\r\n","IsDeferred":false}]}