07.15: prime number, integer(수 나누기 게임)

baekjoon/27172.js

@@ -0,0 +1,48 @@
+// 수 나누기 게임 : 소수, 에라토스테네스의 체, 정수론
+const input = require("fs")
+  .readFileSync("/dev/stdin")
+  .toString()
+  .trim()
+  .split("\n")
+  .map((v) => v.split(" ").map((v) => Number(v)));
+const [n] = input.shift();
+const cards = input.shift();
+const biggest = cards
+  .slice()
+  .sort((a, b) => a - b)
+  .at(-1);
+const count = new Array(biggest + 1).fill(0);
+const isValid = new Array(biggest + 1).fill(null);
+const answer = [];
+
+for (const number of cards) {
+  const yaksu = [];
+  const sqrt = Math.sqrt(number);
+  for (let i = 1; i <= sqrt; i++) {
+    if (number % i === 0) {
+      yaksu.push(i);
+      count[i]++;
+
+      if (number / i !== i) {
+        yaksu.push(number / i);
+        count[number / i]++;
+      }
+    }
+  }
+  isValid[number] = yaksu;
+}
+
+for (let i = 0; i < cards.length; i++) {
+  const number = cards[i];
+  const yaksus = isValid[number].sort((a, b) => a - b);
+
+  let cnt = 0;
+  for (const yaksu of yaksus) {
+    if (isValid[yaksu]) {
+      cnt++;
+    }
+  }
+  answer.push(count[number] - cnt);
+}
+
+console.log(answer.join(" "));