diff --git "a/LiiNi-coder/202512/19 BOJ \355\235\231\352\270\270 \353\263\264\354\210\230\355\225\230\352\270\260.md" "b/LiiNi-coder/202512/19 BOJ \355\235\231\352\270\270 \353\263\264\354\210\230\355\225\230\352\270\260.md"
new file mode 100644
index 00000000..1bdc6d55
--- /dev/null
+++ "b/LiiNi-coder/202512/19 BOJ \355\235\231\352\270\270 \353\263\264\354\210\230\355\225\230\352\270\260.md"	
@@ -0,0 +1,43 @@
+```java
+import java.io.*;
+import java.util.*;
+
+public class Main {
+	public static void main(String[] args) throws IOException {
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+		StringTokenizer st = new StringTokenizer(br.readLine());
+		int N = Integer.parseInt(st.nextToken());
+		int L = Integer.parseInt(st.nextToken());
+
+		int[][] sections = new int[N][2];
+		for(int i = 0; i < N; i++){
+			st = new StringTokenizer(br.readLine());
+			sections[i][0] = Integer.parseInt(st.nextToken());
+			sections[i][1] = Integer.parseInt(st.nextToken());
+		}
+		Arrays.sort(sections, (a, b) -> a[0] - b[0]);
+		int coveredEnd = 0;
+		int answer = 0;
+
+		for(int i = 0; i < N; i++){
+			int start = sections[i][0];
+			int end = sections[i][1];
+			if(coveredEnd >= end){
+				continue;
+			}
+
+			int realStart = Math.max(coveredEnd, start);
+			int remain = end - realStart;
+			int count = remain / L;
+			if(remain % L != 0){
+				count++;
+			}
+			answer += count;
+			coveredEnd = realStart + count * L;
+		}
+
+		System.out.println(answer);
+	}
+}
+
+```