Add solution to 'a lot' of problems

Easy/transpose-matrix/solution.cpp

@@ -0,0 +1,16 @@
+#include <vector>
+
+class Solution {
+public:
+    std::vector<std::vector<int>> transpose(std::vector<std::vector<int>> &matrix) {
+        std::vector<std::vector<int>> trans(matrix[0].size(), std::vector<int>(matrix.size()));
+
+        for (int i = 0; i < matrix.size(); ++i) {
+            for (int j = 0; j < matrix[0].size(); ++j) {
+                trans[j][i] = matrix[i][j];
+            }
+        }
+
+        return trans;
+    }
+};