diff --git a/src/main/java/contest/y2023/BW101.java b/src/main/java/contest/y2023/BW101.java
new file mode 100644
index 0000000..1f98266
--- /dev/null
+++ b/src/main/java/contest/y2023/BW101.java
@@ -0,0 +1,50 @@
+package contest.y2023;
+
+import java.util.*;
+
+public class BW101 {
+    public static void main(String[] args) {
+        BW101 solution = new BW101();
+        solution.maximumCostSubstring("adaa", "d", new int[]{-1000});
+    }
+
+    public int maximumCostSubstring(String s, String chars, int[] vals) {
+        int[] score = new int[26];
+        for (int i = 0; i < 26; i++) {
+            score[i] = i + 1;
+        }
+        for (int i = 0; i < chars.length(); i++) {
+            char ch = chars.charAt(i);
+            score[ch - 'a'] = vals[i];
+        }
+        int bef = 0;
+        int max = 0;
+        for (char ch : s.toCharArray()) {
+            bef = Math.max(bef + score[ch - 'a'], score[ch - 'a']);
+            max = Math.max(max, bef);
+        }
+        return max;
+    }
+
+    public int minNumber(int[] nums1, int[] nums2) {
+        Arrays.sort(nums1);
+        Arrays.sort(nums2);
+        int i1 = 0;
+        int i2 = 0;
+        while (i1 < nums1.length && i2 < nums2.length) {
+            if (nums1[i1] == nums2[i2]) {
+                return nums1[i1];
+            }
+            if (nums1[i1] < nums2[i2]) {
+                i1++;
+            } else {
+                i2++;
+            }
+        }
+        if (nums1[0] < nums2[0]) {
+            return nums1[0] * 10 + nums2[0];
+        } else {
+            return nums2[0] * 10 + nums1[0];
+        }
+    }
+}