✨ feat(pyproject.toml)：添加mplusa依赖用于最大路径和计算

✨ feat(solutions)：新增欧拉问题17、18和67的解决方案
📝 docs(solutions/0018.MaxPathSum1)：添加说明文档指出初始解法存在局部最优问题
✨ feat(solutions/0067.MaxPathSum2)：实现基于最大加代数的优化解法

solutions/0017/eular_17.py

@@ -0,0 +1,71 @@
+"""
+If the numbers 1 to 5 are written out in words: one, two, three, four, five,
+then there are 3 + 3 + 5 + 4 + 4 = 19 letters used in total.
+
+If all the numbers from 1 to 1000 inclusive were written out in words,
+how many letters would be used?
+
+总之感觉这个问题很傻……没什么可说的。
+"""
+
+key: dict[int, str] = {
+    1: "one",
+    2: "two",
+    3: "three",
+    4: "four",
+    5: "five",
+    6: "six",
+    7: "seven",
+    8: "eight",
+    9: "nine",
+    10: "ten",
+    11: "eleven",
+    12: "twelve",
+    13: "thirteen",
+    14: "fourteen",
+    15: "fifteen",
+    16: "sixteen",
+    17: "seventeen",
+    18: "eighteen",
+    19: "nineteen",
+    20: "twenty",
+    30: "thirty",
+    40: "forty",
+    50: "fifty",
+    60: "sixty",
+    70: "seventy",
+    80: "eighty",
+    90: "ninety",
+    100: "hundred",
+    1000: "thousand",
+}
+
+
+def int_to_str(n: int) -> str:
+    if n > 1000:
+        return ""
+    elif n in key:
+        if n == 100:
+            return key[1] + key[n]
+        elif n == 1000:
+            return key[1] + key[1000]
+        else:
+            return key[n]
+    elif n < 100:
+        return key[n - n % 10] + key[n % 10]
+    elif n < 1000:
+        return (
+            key[n // 100]
+            + key[100]
+            + ("" if n % 100 == 0 else "and" + int_to_str(n % 100))
+        )
+    else:
+        return ""
+
+
+def main() -> None:
+    print(sum(len(int_to_str(i)) for i in range(1, 1001)))
+
+
+if __name__ == "__main__":
+    main()