85차 1번 문제풀이

Author: Eric

live8/test85/문제1/황장현.js

@@ -0,0 +1,34 @@
+const input = require('fs')
+  .readFileSync(process.platform === 'linux' ? '/dev/stdin' : './input.txt')
+  .toString()
+  .trim()
+  .split('\n')
+  .map((el) => el.split(' ').map(Number));
+
+function solution(input) {
+  const T = input[0];
+  let index = 1;
+  const result = [];
+  for (let i = 0; i < T; i++) {
+    const N = input[index];
+    const X = input[index + 1].sort((a, b) => a - b);
+    index += 2;
+
+    const XSet = new Set(X);
+
+    let count = 0;
+    for (let p1 = 0; p1 < N - 2; p1++) {
+      for (let p2 = p1 + 2; p2 < N; p2++) {
+        const mid = (X[p1] + X[p2]) / 2;
+        if (Number.isInteger(mid) && XSet.has(mid)) {
+          count++;
+        }
+      }
+    }
+
+    result.push(count);
+  }
+  return result.join('\n');
+}
+
+console.log(solution(input));