diff --git "a/problems/0454.\345\233\233\346\225\260\347\233\270\345\212\240II.md" "b/problems/0454.\345\233\233\346\225\260\347\233\270\345\212\240II.md" index c2a5710fa2..411b60e872 100644 --- "a/problems/0454.\345\233\233\346\225\260\347\233\270\345\212\240II.md" +++ "b/problems/0454.\345\233\233\346\225\260\347\233\270\345\212\240II.md" @@ -97,26 +97,25 @@ Java: ```Java class Solution { public int fourSumCount(int[] nums1, int[] nums2, int[] nums3, int[] nums4) { - Map map = new HashMap<>(); - int temp; int res = 0; + Map map = new HashMap(); //统计两个数组中的元素之和,同时统计出现的次数,放入map for (int i : nums1) { for (int j : nums2) { - temp = i + j; - if (map.containsKey(temp)) { - map.put(temp, map.get(temp) + 1); + int tmp = map.getOrDefault(i + j, 0); + if (tmp == 0) { + map.put(i + j, 1); } else { - map.put(temp, 1); + map.replace(i + j, tmp + 1); } } } //统计剩余的两个元素的和,在map中找是否存在相加为0的情况,同时记录次数 for (int i : nums3) { for (int j : nums4) { - temp = i + j; - if (map.containsKey(0 - temp)) { - res += map.get(0 - temp); + int tmp = map.getOrDefault(0 - i - j, 0); + if (tmp != 0) { + res += tmp; } } }