feat(src): add 64-minPathSum, 66-plusOne, 67-addBinary

Author: kwu130

src/64-minPathSum.cpp

@@ -0,0 +1,50 @@
+//
+// Created by 1412 on 2025/11/8.
+//
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+class Solution {
+public:
+    int minPathSum(vector<vector<int>>& grid) {
+        const int m = grid.size();
+        const int n = grid[0].size();
+        vector<vector<int>> dp(m, vector<int>(n, 0));
+        dp[0][0] = grid[0][0];
+        for (int i = 1; i < m; ++i) {
+            dp[i][0] = dp[i - 1][0] + grid[i][0];
+        }
+        for (int j = 1; j < n; ++j) {
+            dp[0][j] = dp[0][j - 1] + grid[0][j];
+        }
+        for (int i = 1; i < m; ++i) {
+            for (int j = 1; j < n; ++j) {
+                dp[i][j] = min(dp[i - 1][j], dp[i][j - 1]) + grid[i][j];
+            }
+        }
+        return dp[m - 1][n - 1];
+    }
+};
+
+void test() {
+    Solution s;
+    vector<vector<int>> grid = {
+        {1, 3, 1},
+        {1, 5, 1},
+        {4, 2, 1}
+    };
+    assert(s.minPathSum(grid) == 7);
+
+    grid = {
+        {1, 2, 3},
+        {4, 5, 6}
+    };
+    assert(s.minPathSum(grid) == 12);
+}
+
+int main() {
+    test();
+    return 0;
+}

src/66-plusOne.cpp

@@ -0,0 +1,45 @@
+//
+// Created by 1412 on 2025/11/8.
+//
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+class Solution {
+public:
+    vector<int> plusOne(vector<int>& digits) {
+        for (int i = digits.size() - 1; i >= 0; --i) {
+            if (digits[i] < 9) {
+                digits[i]++;
+                return digits;
+            }
+            digits[i] = 0;
+        }
+        digits.insert(digits.begin(), 1);
+        return digits;
+    }
+};
+
+void test() {
+    Solution s;
+    vector<int> digits = {1, 2, 3};
+    vector<int> expected = {1, 2, 4};
+    vector<int> res = s.plusOne(digits);
+    assert(res == expected);
+
+    digits = {4, 3, 2, 1};
+    expected = {4, 3, 2, 2};
+    res = s.plusOne(digits);
+    assert(res == expected);
+
+    digits = {9};
+    expected = {1, 0};
+    res = s.plusOne(digits);
+    assert(res == expected);
+}
+
+int main() {
+    test();
+    return 0;
+}

src/67-addBinary.cpp

@@ -0,0 +1,36 @@
+//
+// Created by 1412 on 2025/11/8.
+//
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+class Solution {
+public:
+    string addBinary(string a, string b) {
+        string res;
+        int i = a.size() - 1, j = b.size() - 1, carry = 0;
+        while (i >= 0 || j >= 0 || carry) {
+            const int x = i >= 0 ? a[i--] - '0' : 0;
+            const int y = j >= 0 ? b[j--] - '0' : 0;
+            const int sum = x + y + carry;
+            res.push_back(sum % 2 + '0');
+            carry = sum / 2;
+        }
+        ranges::reverse(res);
+        return res;
+    }
+};
+
+void test() {
+    Solution s;
+    assert(s.addBinary("11", "1") == "100");
+    assert(s.addBinary("1010", "1011") == "10101");
+    assert(s.addBinary("0", "0") == "0");
+}
+
+int main() {
+    test();
+    return 0;
+}