Solve(binary_search): BOJ 17179 "케이크 자르기" 문제 풀이

Main.java

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+import java.io.*;
+import java.util.*;
+
+class Main {
+    static int n, m, l;
+    static int[] s;
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        n = Integer.parseInt(st.nextToken());
+        m = Integer.parseInt(st.nextToken());
+        l = Integer.parseInt(st.nextToken());
+        s = new int[m];
+        for(int i = 0;i<m;i++) {
+            s[i] = Integer.parseInt(br.readLine());
+        }
+
+        StringBuilder sb = new StringBuilder();
+        for(int i = 0;i<n;i++) {
+            int tmp = binarySearch(Integer.parseInt(br.readLine()));
+            sb.append(tmp + "\n");
+        }
+
+        System.out.print(sb);
+    }
+
+    public static int binarySearch(int q) {
+        int res = 0;
+        int left = 0;
+        int right = l;
+        while(left <= right) {
+            int mid = (left + right) / 2;
+
+            if (canCut(mid, q)) { // 자를수 있으면
+                res = Math.max(res, mid);
+                left = mid + 1;
+            }
+            else {
+                right = mid - 1;
+            }
+        }
+        return res;
+    }
+
+    private static boolean canCut(int minLen, int q) {
+        int count = 0;
+        int last = 0; 
+
+        for (int i = 0; i < m; i++) {
+            if (s[i] - last >= minLen) {
+                count++;
+                last = s[i];
+            }
+
+            if (count == q && (l - last) >= minLen) {
+                return true;
+            }
+        }
+        return false;
+    }
+}
+
+// 10 10 15 20 5 10