[minzino] bj1943 - 동전 분배 풀이 실패(dp)

minzino/java/src/main/java/org/example/mar/bj1943/Main.java

@@ -0,0 +1,59 @@
+package main.java.org.example.mar.bj1943;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.StringTokenizer;
+
+public class Main {
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringBuilder sb = new StringBuilder();
+
+        for (int t = 0; t < 3; t++) {
+            int n = Integer.parseInt(br.readLine());
+            int[] coins = new int[n];
+            int[] counts = new int[n];
+            int totalValue = 0;
+
+            for (int i = 0; i < n; i++) {
+                StringTokenizer st = new StringTokenizer(br.readLine());
+                coins[i] = Integer.parseInt(st.nextToken());
+                counts[i] = Integer.parseInt(st.nextToken());
+                totalValue += coins[i] * counts[i];
+            }
+
+            if (totalValue % 2 != 0) {
+                sb.append(0).append('\n');
+            } else {
+                boolean[] dp = new boolean[totalValue / 2 + 1];
+                dp[0] = true;
+
+                for (int i = 0; i < n; i++) {
+                    int coin = coins[i];
+                    int count = counts[i];
+                    for (int k = 1; k <= count; k *= 2) {
+                        for (int j = totalValue / 2; j >= k * coin; j--) {
+                            dp[j] |= dp[j - k * coin];
+                        }
+                        count -= k;
+                    }
+                    if (count > 0) {
+                        for (int j = totalValue / 2; j >= count * coin; j--) {
+                            dp[j] |= dp[j - count * coin];
+                        }
+                    }
+                }
+
+                if (dp[totalValue / 2]) {
+                    sb.append(1).append('\n');
+                } else {
+                    sb.append(0).append('\n');
+                }
+            }
+        }
+        System.out.print(sb);
+    }
+}
+