chore: import upstream snapshot with attribution

strings/brute_force_string_searching.cpp

@@ -0,0 +1,58 @@
+/**
+ * @file
+ * @brief          String pattern search - brute force
+ */
+#include <iostream>
+#ifdef _MSC_VER
+#include <string>  // use this for MS Visual C++
+#else
+#include <cstring>
+#endif
+#include <vector>
+
+namespace string_search {
+/**
+ * Find a pattern in a string by comparing the pattern to every substring.
+ * @param text     Any string that might contain the pattern.
+ * @param pattern  String that we are searching for.
+ * @return         Index where the pattern starts in the text
+ * @return         -1 if the pattern was not found.
+ */
+int brute_force(const std::string &text, const std::string &pattern) {
+    size_t pat_l = pattern.length();
+    size_t txt_l = text.length();
+    int index = -1;
+    if (pat_l <= txt_l) {
+        for (size_t i = 0; i < txt_l - pat_l + 1; i++) {
+            std::string s = text.substr(i, pat_l);
+            if (s == pattern) {
+                index = i;
+                break;
+            }
+        }
+    }
+    return index;
+}
+}  // namespace string_search
+
+using string_search::brute_force;
+
+/** set of test cases */
+const std::vector<std::vector<std::string>> test_set = {
+    // {text, pattern, expected output}
+    {"a", "aa", "-1"},  {"a", "a", "0"},    {"ba", "b", "0"},
+    {"bba", "bb", "0"}, {"bbca", "c", "2"}, {"ab", "b", "1"}};
+
+/** Main function */
+int main() {
+    for (const auto &i : test_set) {
+        int output = brute_force(i[0], i[1]);
+
+        if (std::to_string(output) == i[2]) {
+            std::cout << "success\n";
+        } else {
+            std::cout << "failure\n";
+        }
+    }
+    return 0;
+}