Week21_Changmin

k/programmers/구현/Lv2_오픈채팅방_1.js

@@ -0,0 +1,24 @@
+function solution(record) {
+    const userInfo = {};
+    const ans = [];
+
+    // 유저 정보
+    record.map((item) => {
+        const [command, uid, nickname] = item.split(' ');
+
+        if (command === 'Enter') {
+            userInfo[uid] = nickname;
+            ans.push(`${uid}님이 들어왔습니다.`);
+        } else if (command === 'Change') {
+            userInfo[uid] = nickname;
+        } else if (command === 'Leave') {
+            ans.push(`${uid}님이 나갔습니다.`);
+        }
+    });
+    // 입장, 퇴장 기록
+    for (let i=0; i < ans.length; i++) {
+        let uid = ans[i].split('님')[0];
+        ans[i] = ans[i].replace(uid, userInfo[uid]);
+    }
+    return ans;
+}

k/programmers/구현/Lv2_주차 요금 계산_1.js

@@ -0,0 +1,42 @@
+function solution(fees, records) {
+    const answer = [];
+    const carIn = {};
+    let carOut = {};
+    const [baseT, baseF, unitT, unitF] = fees;
+
+    // 시간 계산
+    records.map((item) => {
+        const [clock, num, record] = item.split(' ');
+        const [hour, min] = clock.split(':');
+        const time = parseInt(hour) * 60 + parseInt(min);
+
+        if (record === 'IN') {
+            carIn[num] = time;
+        } else {
+            carOut.hasOwnProperty(num)
+                ? carOut[num] = carOut[num] + time - carIn[num]
+                : carOut[num] = time - carIn[num];
+            delete carIn[num];
+        }
+    });
+    // 오늘 출차하지 않은 차량
+    for (const [num, time] of Object.entries(carIn)) {
+        carOut.hasOwnProperty(num)
+            ? carOut[num] = carOut[num] + 1439 - time
+            : carOut[num] = 1439 - time;
+        delete carIn[num];
+    }
+    // 차량번호 오름차순 정렬
+    carOut = Object.entries(carOut).sort((a,b) => a[0] - b[0]);
+
+    // 요금 계산
+    carOut.map((item) => {
+        const time = item[1];
+        answer.push(
+            time <= baseT
+                ? baseF
+                : baseF + Math.ceil((time - baseT) / unitT) * unitF
+        );
+    })
+    return answer;
+}

k/programmers/문자열/Lv1_다트 게임_1.js

@@ -0,0 +1,29 @@
+function solution(dartResult) {
+    const answer = [];
+    let tmp;
+
+    for (let i=0; i < dartResult.length; i++) {
+        let item = dartResult[i];
+
+        if (!isNaN(Number(item))) {  // 정수라면
+            tmp = dartResult[i-1] == 1 ? 10 : Number(item);
+        } else {
+            switch (item) {
+                case 'S': answer.push(tmp);
+                    break;
+                case 'D': answer.push(Math.pow(tmp, 2));
+                    break;
+                case 'T': answer.push(Math.pow(tmp, 3));
+                    break;
+                case '*':
+                    answer[answer.length-2] = answer[answer.length-2] * 2;
+                    answer[answer.length-1] = answer[answer.length-1] * 2;
+                    break;
+                case '#':
+                    answer[answer.length-1] = answer[answer.length-1] * (-1);
+                    break;
+            }
+        }
+    }
+    return answer.reduce((acc, cur) => acc + cur, 0);
+}

k/programmers/문자열/Lv2_압축_1.js

@@ -0,0 +1,22 @@
+function solution(msg) {
+    const alphabet = ['A', 'B', 'C', 'D', 'E', 'F', 'G',
+                     'H', 'I', 'J', 'K', 'L', 'M', 'N',
+                     'O', 'P', 'Q', 'R', 'S', 'T', 'U',
+                     'V', 'W', 'X', 'Y', 'Z'];
+    let tmp = '';
+    const answer = [];
+
+    for (let i=0; i < msg.length; i++) {
+        tmp += msg[i];
+
+        if (!alphabet.includes(tmp)) {
+            answer.push(alphabet.indexOf(tmp.slice(0, -1)) +1);  // 색인 번호
+            alphabet.push(tmp);
+            tmp = msg[i];  // 현재 시점
+        }
+    }
+    if (tmp) {
+        answer.push(alphabet.indexOf(tmp) +1)
+    }
+    return answer;
+}

k/programmers/반복문/Lv2_n진수 게임_1.js

@@ -0,0 +1,16 @@
+function solution(n, t, m, p) {
+    let num = '';
+    let ans = '';
+
+    for (let i = 0; num.length < m * t; i++) {
+        num += i.toString(n).toUpperCase();
+    }
+    num.split('').map((item, idx) => {
+        if (idx % m  === (p-1)) {
+            if (ans.length < t) {
+                ans += item;
+            }
+        }
+    });
+    return ans;
+}

k/programmers/수학/Lv2_k진수에서 소수 개수 구하기_1.js

@@ -0,0 +1,22 @@
+function solution(n, k) {
+    let count = 0;
+    n.toString(k).split("0")
+     .map((num) => {
+        if (isPrime(Number(num))) {
+            count++;
+        }
+    });
+    return count;
+}
+
+function isPrime(num) {
+    if (num <= 1) {
+        return false;
+    }
+    for (let i=2; i < Math.sqrt(num); i++) {
+        if (num % i === 0) {  // 약수가 있다면 소수가 아니다
+            return false;
+        }
+    }
+    return true;
+}