[이종환-17주차 알고리즘 스터디]

이종환/17주차/공통_부분_문자열.java

@@ -0,0 +1,27 @@
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+
+public class ����_�κ�_���ڿ� {
+
+	public static void main(String[] args) throws IOException {
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+		String[] input1 = br.readLine().split("");
+		String[] input2 = br.readLine().split("");
+		int[][] dp = new int[input1.length][input2.length];
+		int ans = 0;
+		int temp = 0;
+		for (int i = 0; i < input1.length; i++) {
+			for (int j = 0; j < input2.length; j++) {
+				if(input1[i].equals(input2[j])) {
+					dp[i][j] = 1;
+					if(i == 0 || j == 0) continue;
+
+					dp[i][j] += dp[i-1][j-1];
+					ans = Math.max(ans, dp[i][j]);
+				}
+			}
+		}
+		System.out.println(ans);
+	}
+}

이종환/17주차/어항정리.java

@@ -0,0 +1,170 @@
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.StringTokenizer;
+
+public class �������� {
+
+
+	static int size,tryCnt,goalDiff;
+	static int height,cnt,floor,stIdx;
+	static int[][] folded;
+	static int[][] temp;
+	static int[] arr;
+	static int[] dy = {-1,0,1,0};
+	static int[] dx = {0,1,0,-1};
+
+	public static void main(String[] args) throws IOException {
+		init();
+		process();
+		print();
+	}
+
+	private static void print() {System.out.println(tryCnt);}
+
+	private static void process() {
+		while(!isEnd()) {
+			tryCnt++;
+			plusSmallest();
+			foldOne();
+			foldHalf();
+		}
+	}
+
+	private static void plusSmallest() {
+		int smallest = Integer.MAX_VALUE;
+		ArrayList<Integer> idxes = new ArrayList<>();
+		for (int i = 0; i < size; i++) {
+			if (arr[i] == smallest) idxes.add(i);
+			else if (arr[i] < smallest) {
+				idxes.clear();
+				smallest = arr[i];
+				idxes.add(i);
+			}
+		}
+		for (int i = 0; i < idxes.size(); i++) {
+			arr[idxes.get(i)]++;
+		}
+
+	}
+
+
+	private static void foldOne() {
+		folded = new int[size][size];
+		height=1; //��� ����. ó������ ����1¥�� ����� �����Ѵٰ� ����
+		floor=1; //�ٴ� ����.
+		cnt = 1; // ��� ����
+		stIdx = 0;
+
+		for (int i = 0; i < size; i++) folded[0][i] = arr[i];
+		while(isValid()) {
+			int nIdx = stIdx+cnt; // ��� ���� �ٴ��� ù��° �ε���
+			for (int j = 0; j < cnt; j++) {
+				for (int i = 0; i < height; i++) {
+					folded[cnt-j+floor-1][nIdx+i] = folded[i][j+stIdx];
+					folded[i][j+stIdx] = 0;
+				}
+			}
+			stIdx = height*cnt; // ���� nIdx�� ù��° ����� ��ġ�� ��
+			if(height == cnt)height++;
+			else cnt++;
+		}
+		redistributeAll();
+	}
+
+
+	private static boolean isValid() {
+		if (height == cnt) return size >= (height+1)*cnt;
+		return size >= height*(cnt+1);
+	}
+
+
+	private static void foldHalf() {
+		folded = new int[size][size];
+		// 4��� ���� ��, ������ ��Ʈ�� �����ϴ� �ε���
+		int[] pIdx = {0, size/4,(size/4)*2,(size/4)*3};
+		int quater = size/4;
+		for (int i = 0; i < quater; i++) {
+			folded[0][pIdx[3]+i] = arr[pIdx[3]+i];
+			folded[1][pIdx[3]+i] = arr[pIdx[1]-1-i];
+			folded[2][pIdx[3]+i] = arr[pIdx[1]+i];
+			folded[3][pIdx[3]+i] = arr[pIdx[3]-1-i];
+		}
+
+		redistributeAll();		
+	}
+
+
+	//��ü ��й�
+	private static void redistributeAll() {
+		temp = new int[size][size];
+		for (int i = 0; i < size; i++) {
+			for (int j = 0; j < size; j++) {
+				redistribute(i,j);
+			}
+		}
+		for (int i = 0; i < size; i++) {
+			for (int j = 0; j < size; j++) {
+				// ��ȭ���� folded�� �ݿ�
+				folded[i][j] += temp[i][j];
+			}
+		}
+
+		sort();
+	}
+
+	private static void redistribute(int y, int x) {
+		for (int i = 0; i < 4; i++) {
+			int ny = y + dy[i];
+			int nx = x + dx[i];
+
+			if ( ny < 0 || nx <0 || ny >= size|| nx >= size)continue;
+			if (folded[ny][nx] == 0 || folded[y][x] <= folded[ny][nx])continue;
+
+			//���
+			int amount = (folded[y][x] - folded[ny][nx])/5;
+			temp[y][x] -= amount;
+			temp[ny][nx] += amount;
+		}
+
+	}
+
+	// �׿��ִ°��� �������.
+	private static void sort() {
+		int arrIdx = 0;
+
+		for (int i = 0; i < size; i++) {
+			if (arrIdx == size) break;
+			if (folded[0][i] == 0) continue; 
+			int idx = 0;
+			while(true) {
+				arr[arrIdx++] = folded[idx++][i];
+				if(idx >= size || folded[idx][i] == 0) break;
+			}
+		}
+	}
+
+	private static boolean isEnd() {
+		int largest = Integer.MIN_VALUE;
+		int smallest = Integer.MAX_VALUE;
+		for (int i = 0; i < size; i++) {
+			largest = Math.max(largest, arr[i]);
+			smallest = Math.min(smallest, arr[i]);
+		}
+		return largest-smallest <= goalDiff;
+	}
+
+	private static void init() throws IOException {
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+		StringTokenizer st = new StringTokenizer(br.readLine());
+
+		size = Integer.parseInt(st.nextToken());
+		goalDiff = Integer.parseInt(st.nextToken());
+		tryCnt = 0;
+		arr = new int[size];
+
+		st = new StringTokenizer(br.readLine());
+		for (int i = 0; i < size; i++) arr[i] = Integer.parseInt(st.nextToken());
+	}
+}

이종환/17주차/전구와_스위치.java

@@ -0,0 +1,79 @@
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.Arrays;
+
+public class ������_����ġ {
+	static String[] input1,input2;
+	static int[] choice,flip;
+	static int len,ans;
+	public static void main(String[] args) throws IOException {
+		init();
+		process();
+		print();
+	}
+
+	private static void print() {System.out.println((ans==Integer.MAX_VALUE)?-1:ans);}
+
+	private static void process() {
+		getFlip();
+		//������ġ ����ġ�� �ȴ����� ����
+		choice[0] = 0; 
+		greedy();
+		//������ġ ����ġ�� ������ ����
+		choice[0] = 1;
+		greedy();
+	}
+
+
+	private static void getFlip() {
+		// �������� �Ǵ� �κ� ã��
+		for (int i = 0; i < len; i++) flip[i] = !(input1[i].equals(input2[i]))?1:0;
+
+	}
+
+	private static void greedy() {
+		for (int i = 1; i < len; i++) {
+			int goal = flip[i-1]; // �̰� ���������
+			int cur = (choice[i-1] + ((i > 1)?choice[i-2]:0))%2;// ���� �ΰ��������� ��Ȳ
+			choice[i] = Math.abs(goal-cur);
+
+		}
+
+		check();
+
+	}
+
+
+	private static void check() {
+		int temp = 0;
+		for (int i = 0; i < len; i++) {
+			temp += choice[i];
+			int goal = flip[i];
+			int cur = choice[i];
+
+			if (i > 0) cur += choice[i-1];
+			if (i < len-1) cur += choice[i+1];
+			cur %= 2;
+
+
+			if(goal != cur) return;
+
+		}
+
+		ans = Math.min(temp, ans);
+
+	}
+
+	private static void init() throws IOException {
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+		len = Integer.parseInt(br.readLine());
+		input1 = br.readLine().split("");
+		input2 = br.readLine().split("");
+
+		choice = new int[len];
+		flip = new int[len];
+		ans = Integer.MAX_VALUE;
+
+	}
+}

이종환/17주차/줄_세우기.java

@@ -0,0 +1,30 @@
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.Arrays;
+
+public class ��_����� {
+	public static void main(String[] args) throws NumberFormatException, IOException {
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+		//���� ���� ���� (LIS, Longest Increasing Subsequence)
+		int size = Integer.parseInt(br.readLine());
+		int[] arr = new int[size];
+		int[] dp = new int[size];
+		for (int i = 0; i < size; i++) arr[i] = Integer.parseInt(br.readLine());
+
+		Arrays.fill(dp, 1);
+		for (int i = 1; i < size; i++) {
+			for (int j = 0; j <i; j++) {
+				if (arr[i] < arr[j]) continue;
+				dp[i] = Math.max(dp[i], dp[j]+1);
+
+			}
+		}
+		int max = 1;
+		for (int i = 0; i < size; i++) max = Math.max(max, dp[i]);
+		System.out.println(size-max);
+
+	}
+
+
+}