uploaded at 2022. 12. 18. 오전 2:05:32

programmers/평행/solution.java

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+// [문제 링크]: https://school.programmers.co.kr/learn/courses/30/lessons/120875
+
+import java.util.HashMap;
+class Solution {
+    public int solution(int[][] dots) {
+        int answer = 0;
+        HashMap<Double, Integer> hash = new HashMap<>();
+        for(int a = 0; a < dots.length-1; a++){
+            for(int b = a+1; b < dots.length; b++){
+                hash.put((double) (dots[a][1]-dots[b][1])/(dots[a][0]-dots[b][0]),hash.getOrDefault((double) (dots[a][1]-dots[b][1])/(dots[a][0]-dots[b][0]),0)+1);
+            }
+        }
+        for(double key : hash.keySet()){
+            if(hash.get(key)>1) {
+                answer = 1;
+                break;
+            }
+        }
+        return answer;
+    }
+}