add

Author: lzwjava

uva/165/src/StampOptimization.java

@@ -0,0 +1,89 @@
+// chatgpt
+import java.util.Arrays;
+
+public class StampOptimization {
+
+    private static int maxValue = 0;
+    private static int[] bestStamps = new int[10];
+    private static int H, K;
+    private static int[] currStamps = new int[10];
+    private static int[][] dp = new int[200][10];
+
+    public static void main(String[] args) {
+        java.util.Scanner scanner = new java.util.Scanner(System.in);
+
+        while (true) {
+            H = scanner.nextInt();
+            K = scanner.nextInt();
+            if (H == 0 && K == 0) break;
+
+            // Initialize the dp table
+            for (int[] row : dp) {
+                Arrays.fill(row, 0);
+            }
+            dp[0][0] = 1;
+            maxValue = 0;
+
+            // Start the DFS to find the optimal denominations
+            dfs(0, 0, 0);
+
+            // Output the result
+            for (int i = 0; i < K; i++) {
+                System.out.printf("%3d", bestStamps[i]);
+            }
+            System.out.printf(" ->%3d%n", maxValue);
+        }
+        scanner.close();
+    }
+
+    private static void dfs(int idx, int lastStamp, int maxReach) {
+        int currMax = 0;
+
+        // Calculate the maximum consecutive value that can be reached
+        for (int i = maxReach; ; i++) {
+            int j;
+            for (j = 0; j <= H; j++) {
+                if (dp[i][j] != 0) break;
+            }
+            if (j == H + 1) {
+                currMax = i - 1;
+                break;
+            }
+        }
+
+        // Check if we have selected all denominations
+        if (idx == K) {
+            if (currMax >= maxValue) {
+                maxValue = currMax;
+                System.arraycopy(currStamps, 0, bestStamps, 0, K);
+            }
+            return;
+        }
+
+        // Try adding a new denomination
+        int[][] steps = new int[10000][2];
+        for (int i = lastStamp + 1; i <= currMax + 1; i++) {
+            int stepCount = 0;
+
+            // Update dp table with the current denomination
+            for (int j = 0; j <= 100; j++) {
+                for (int k = 0; k < H; k++) {
+                    if (dp[j + i][k + 1] == 0 && dp[j][k] != 0) {
+                        dp[j + i][k + 1] = 1;
+                        steps[stepCount][0] = j + i;
+                        steps[stepCount][1] = k + 1;
+                        stepCount++;
+                    }
+                }
+            }
+
+            currStamps[idx] = i;
+            dfs(idx + 1, i, currMax);
+
+            // Backtrack to undo dp updates
+            for (int j = 0; j < stepCount; j++) {
+                dp[steps[j][0]][steps[j][1]] = 0;
+            }
+        }
+    }
+}