36 week

Author: leesangeok

week36/이상억/backjoon/도영이가_만든_맛있는_음식.java

@@ -2,50 +2,46 @@
 import java.util.*;
 
 public class Main {
-    public static void main(String[] args) throws Exception {
-        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
-        StringTokenizer st;
-
-        st = new StringTokenizer(br.readLine());
-        int N = Integer.parseInt(st.nextToken());
-        int K = Integer.parseInt(st.nextToken());
-        int Q = Integer.parseInt(st.nextToken());
-        int M = Integer.parseInt(st.nextToken());
-
-        boolean[] sleep = new boolean[N + 3];   // 졸고 있는 학생
-        boolean[] attend = new boolean[N + 3];  // 출석한 학생
-
-        st = new StringTokenizer(br.readLine());
-        for (int i = 0; i < K; i++) {
-            sleep[Integer.parseInt(st.nextToken())] = true;
-        }
 
-        st = new StringTokenizer(br.readLine());
-        for (int i = 0; i < Q; i++) {
-            int x = Integer.parseInt(st.nextToken());
-            if (sleep[x]) continue; // 졸고 있으면 전파 X
+    static int N;
+    static int[] S, B;
+    static int answer = Integer.MAX_VALUE;
 
-            for (int j = x; j <= N + 2; j += x) {
-                if (!sleep[j]) {
-                    attend[j] = true;
-                }
+    static void dfs(int idx, long sour, long bitter, boolean used) {
+        if (idx == N) {
+            if (used) {
+                answer = Math.min(answer, (int)Math.abs(sour - bitter));
             }
+            return;
         }
 
-        int[] prefix = new int[N + 3];
-        for (int i = 3; i <= N + 2; i++) {
-            prefix[i] = prefix[i - 1] + (attend[i] ? 0 : 1);
-        }
+        // 현재 재료 사용
+        dfs(idx + 1,
+                sour * S[idx],
+                bitter + B[idx],
+                true);
+
+        // 현재 재료 사용 안 함
+        dfs(idx + 1,
+                sour,
+                bitter,
+                used);
+    }
+
+    public static void main(String[] args) throws Exception {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        N = Integer.parseInt(br.readLine());
 
-        StringBuilder sb = new StringBuilder();
+        S = new int[N];
+        B = new int[N];
 
-        for (int i = 0; i < M; i++) {
-            st = new StringTokenizer(br.readLine());
-            int S = Integer.parseInt(st.nextToken());
-            int E = Integer.parseInt(st.nextToken());
-            sb.append(prefix[E] - prefix[S - 1]).append('\n');
+        for (int i = 0; i < N; i++) {
+            StringTokenizer st = new StringTokenizer(br.readLine());
+            S[i] = Integer.parseInt(st.nextToken());
+            B[i] = Integer.parseInt(st.nextToken());
         }
 
-        System.out.print(sb);
+        dfs(0, 1, 0, false);
+        System.out.println(answer);
     }
 }

week36/이상억/backjoon/여행_가자.java

@@ -3,7 +3,52 @@
 
 
 public class Main{
+
+   static int[] parent;
+
+   static int find(int x){
+       if(parent[x] == x) return x;
+       return parent[x] = find(parent[x]);
+   }
+
+    static void union(int a, int b){
+        a = find(a);
+        b = find(b);
+        if (a != b) parent[b] = a;
+    }
+
+
     public static void main(String[] args) throws IOException{
         BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+
+        int N = Integer.parseInt(br.readLine());
+        int M = Integer.parseInt(br.readLine());
+
+        parent = new int[N + 1];
+        for(int i = 1; i <= N; i++) parent[i] = i;
+
+        for(int i = 1; i <= N; i ++){
+            StringTokenizer st = new StringTokenizer(br.readLine());
+            for(int j = 1; j <= N; j++){
+                int connected  = Integer.parseInt(st.nextToken());
+                if(connected == 1){
+                    union(i,j);
+                }
+            }
+        }
+
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        int first_city = Integer.parseInt(st.nextToken());
+        int root = find(first_city);
+
+        while(st.hasMoreTokens()){
+            int city = Integer.parseInt(st.nextToken());
+            if(find(city) != root){
+                System.out.println("NO");
+                return;
+            }
+        }
+
+        System.out.println("YES");
     }
 }

week36/이상억/backjoon/출석체크.java

@@ -1,9 +1,51 @@
 import java.io.*;
 import java.util.*;
 
-
-public class Main{
-    public static void main(String[] args) throws IOException{
+public class Main {
+    public static void main(String[] args) throws Exception {
         BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st;
+
+        st = new StringTokenizer(br.readLine());
+        int N = Integer.parseInt(st.nextToken());
+        int K = Integer.parseInt(st.nextToken());
+        int Q = Integer.parseInt(st.nextToken());
+        int M = Integer.parseInt(st.nextToken());
+
+        boolean[] sleep = new boolean[N + 3];   // 졸고 있는 학생
+        boolean[] attend = new boolean[N + 3];  // 출석한 학생
+
+        st = new StringTokenizer(br.readLine());
+        for (int i = 0; i < K; i++) {
+            sleep[Integer.parseInt(st.nextToken())] = true;
+        }
+
+        st = new StringTokenizer(br.readLine());
+        for (int i = 0; i < Q; i++) {
+            int x = Integer.parseInt(st.nextToken());
+            if (sleep[x]) continue; // 졸고 있으면 전파 X
+
+            for (int j = x; j <= N + 2; j += x) {
+                if (!sleep[j]) {
+                    attend[j] = true;
+                }
+            }
+        }
+
+        int[] prefix = new int[N + 3];
+        for (int i = 3; i <= N + 2; i++) {
+            prefix[i] = prefix[i - 1] + (attend[i] ? 0 : 1);
+        }
+
+        StringBuilder sb = new StringBuilder();
+
+        for (int i = 0; i < M; i++) {
+            st = new StringTokenizer(br.readLine());
+            int S = Integer.parseInt(st.nextToken());
+            int E = Integer.parseInt(st.nextToken());
+            sb.append(prefix[E] - prefix[S - 1]).append('\n');
+        }
+
+        System.out.print(sb);
     }
 }