[20250715] BOJ / G1 / 놀이 공원 / 이종환

0224LJH/202507/15 BOJ 놀이 공원.md

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+```java
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.*;
+
+public class Main {
+    static int kidCnt, toyCnt,  ans;
+    static long start, end,minTime;
+    static int[] toyTime;
+
+    public static void main(String[] args) throws IOException {
+        init();
+        process();
+        print();
+    }
+
+    private static void init() throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        kidCnt = Integer.parseInt(st.nextToken());
+        toyCnt = Integer.parseInt(st.nextToken());
+        toyTime = new int[toyCnt];
+
+        start = 0;
+        end = 2000_000_000_00l;
+
+        st = new StringTokenizer(br.readLine());
+        for (int i = 0; i < toyCnt; i++) {
+            toyTime[i] = Integer.parseInt(st.nextToken());
+        }
+    }
+
+    private static void process() {
+        if (kidCnt <= toyCnt) {
+            ans = kidCnt;
+            return;
+        }
+
+        //마지막 사람이 탑승하는 시간 구함
+        calculateProperTime();
+
+        int curKidCnt = 0;
+        List<Integer> minRemainIdx = new ArrayList<>();
+        int minRemain = 30;
+
+        for (int i = 0; i < toyCnt; i++) {
+            curKidCnt += minTime / toyTime[i] + 1;
+
+            if (minRemain > minTime % toyTime[i]) {
+                minRemain = (int) (minTime % toyTime[i]);
+                minRemainIdx = new ArrayList<>();
+                minRemainIdx.add(i);
+            } else if (minRemain == minTime % toyTime[i]) {
+                minRemainIdx.add(i);
+            }
+        }
+
+        if (curKidCnt == kidCnt){
+            ans = minRemainIdx.get(minRemainIdx.size()-1)+1;
+        } else{
+            int diff = (curKidCnt - kidCnt)%minRemainIdx.size();
+            ans = minRemainIdx.get(minRemainIdx.size()-1-diff) + 1;
+        }
+
+    }
+
+    private static void calculateProperTime() {
+        long mid =  ((start + end) / 2);
+        minTime = Long.MAX_VALUE;
+
+
+        while (start < end) {
+
+            //이번 탐색에서 놀이기구를 이용한 총 인원
+            long peopleCnt = 0;
+
+            for (int i = 0; i < toyCnt; i++) {
+                //총시간을 각 놀이기구 이용시간으로 나눈 몫 + 1;
+                peopleCnt += mid/toyTime[i] + 1;
+            }
+
+            // 크거나 같음 -> 암튼 이 시간내에 꼬마들이 다 이용함.
+            if(peopleCnt >= kidCnt) {
+                if (mid < minTime) {
+                    minTime = mid;
+                    end = mid;
+                }
+
+                if (peopleCnt == kidCnt){
+                    minTime = mid;
+                    break;
+                }
+            } else  {
+                // 목표보다 아이들이 이용 못함 -> 더 큰쪽 조사
+                start = mid+1;
+            }
+
+            mid = ((start + end) / 2);
+        }
+
+
+    }
+
+
+    private static void print()  {
+        System.out.println(ans);
+    }
+
+
+
+}
+
+```