Merge branch 'master' into myContribution

Author: realstealthninja

bit_manipulation/count_of_set_bits.cpp

@@ -36,11 +36,19 @@ namespace count_of_set_bits {
  * @returns total number of set-bits in the binary representation of number `n`
  */
 std::uint64_t countSetBits(
-    std ::int64_t n) {  // int64_t is preferred over int so that
+    std ::uint64_t n) {  // uint64_t is preferred over int so that
                         // no Overflow can be there.
+                        //It's preferred over int64_t because it Guarantees that inputs are always non-negative, 
+                        //which matches the algorithmic problem statement.
+                        //set bit counting is conceptually defined only for non-negative numbers.
+                        //Provides a type Safety: Using an unsigned type helps prevent accidental negative values,
+
+    std::uint64_t count = 0;  // "count" variable is used to count number of set-bits('1')
+                            // in binary representation of number 'n'
+                            //Count is uint64_t because it Prevents theoretical overflow if someone passes very large integers.
+                            //  Behavior stays the same for all normal inputs.
+                            // Safer for edge cases.
 
-    int count = 0;  // "count" variable is used to count number of set-bits('1')
-                    // in binary representation of number 'n'
     while (n != 0) {
         ++count;
         n = (n & (n - 1));

math/number_of_positive_divisors.cpp

@@ -23,7 +23,6 @@
 **/
 
 #include <cassert>
-#include <iostream>
 
 /**
  * Function to compute the number of positive divisors.
@@ -80,13 +79,5 @@ void tests() {
  */
 int main() {
     tests();
-    int n;
-    std::cin >> n;
-    if (n == 0) {
-        std::cout << "All non-zero numbers are divisors of 0 !" << std::endl;
-    } else {
-        std::cout << "Number of positive divisors is : ";
-        std::cout << number_of_positive_divisors(n) << std::endl;
-    }
     return 0;
 }

others/postfix_evaluation.cpp

@@ -12,11 +12,11 @@
  * When the expression is ended, the number in the stack is the final answer
  */
 #include <algorithm>  // for all_of
-#include <array>      // for array
 #include <cassert>    // for assert
 #include <iostream>   // for io operations
 #include <stack>      // for std::stack
 #include <string>     // for stof
+#include <vector>     // for std::vector
 
 /**
  * @namespace others
@@ -77,37 +77,43 @@ void evaluate(float a, float b, const std::string &operation,
     }
 }
 
+namespace {
+float remove_from_stack(std::stack<float> &stack) {
+    if (stack.empty()) {
+        throw std::invalid_argument("Not enough operands");
+    }
+    const auto res = stack.top();
+    stack.pop();
+    return res;
+}
+}  // namespace
+
 /**
  * @brief Postfix Evaluation algorithm to compute the value from given input
  * array
- * @tparam N number of array size
- * @param input Array of characters consisting of numbers and operations
+ * @param input vector of strings consisting of numbers and operations
  * @returns stack[stackTop] returns the top value from the stack
  */
-template <std::size_t N>
-float postfix_evaluation(std::array<std::string, N> input) {
+float postfix_evaluation(const std::vector<std::string> &input) {
     std::stack<float> stack;
-    int j = 0;
 
-    while (j < N) {
-        std::string scan = input[j];
+    for (const auto &scan : input) {
         if (is_number(scan)) {
             stack.push(std::stof(scan));
 
         } else {
-            const float op2 = stack.top();
-            stack.pop();
-            const float op1 = stack.top();
-            stack.pop();
+            const auto op2 = remove_from_stack(stack);
+            const auto op1 = remove_from_stack(stack);
 
             evaluate(op1, op2, scan, stack);
         }
-        j++;
     }
 
-    std::cout << stack.top() << "\n";
-
-    return stack.top();
+    const auto res = remove_from_stack(stack);
+    if (!stack.empty()) {
+        throw std::invalid_argument("Too many operands");
+    }
+    return res;
 }
 }  // namespace postfix_expression
 }  // namespace others
@@ -118,7 +124,7 @@ float postfix_evaluation(std::array<std::string, N> input) {
  * @returns none
  */
 static void test_function_1() {
-    std::array<std::string, 7> input = {"2", "3", "1", "*", "+", "9", "-"};
+    std::vector<std::string> input = {"2", "3", "1", "*", "+", "9", "-"};
 
     float answer = others::postfix_expression::postfix_evaluation(input);
 
@@ -131,15 +137,15 @@ static void test_function_1() {
  * @returns none
  */
 static void test_function_2() {
-    std::array<std::string, 9> input = {"100", "200", "+", "2", "/",
-                                        "5",   "*",   "7", "+"};
+    std::vector<std::string> input = {"100", "200", "+", "2", "/",
+                                      "5",   "*",   "7", "+"};
     float answer = others::postfix_expression::postfix_evaluation(input);
 
     assert(answer == 757);
 }
 
 static void test_function_3() {
-    std::array<std::string, 43> input = {
+    std::vector<std::string> input = {
         "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1",
         "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1",
         "+", "+", "+", "+", "+", "+", "+", "+", "+", "+", "+",
@@ -149,6 +155,46 @@ static void test_function_3() {
     assert(answer == 22);
 }
 
+static void test_single_input() {
+    std::vector<std::string> input = {"1"};
+    float answer = others::postfix_expression::postfix_evaluation(input);
+
+    assert(answer == 1);
+}
+
+static void test_not_enough_operands() {
+    std::vector<std::string> input = {"+"};
+    bool throws = false;
+    try {
+        others::postfix_expression::postfix_evaluation(input);
+    } catch (std::invalid_argument &) {
+        throws = true;
+    }
+    assert(throws);
+}
+
+static void test_not_enough_operands_empty_input() {
+    std::vector<std::string> input = {};
+    bool throws = false;
+    try {
+        others::postfix_expression::postfix_evaluation(input);
+    } catch (std::invalid_argument &) {
+        throws = true;
+    }
+    assert(throws);
+}
+
+static void test_too_many_operands() {
+    std::vector<std::string> input = {"1", "2"};
+    bool throws = false;
+    try {
+        others::postfix_expression::postfix_evaluation(input);
+    } catch (std::invalid_argument &) {
+        throws = true;
+    }
+    assert(throws);
+}
+
 /**
  * @brief Main function
  * @returns 0 on exit
@@ -157,6 +203,10 @@ int main() {
     test_function_1();
     test_function_2();
     test_function_3();
+    test_single_input();
+    test_not_enough_operands();
+    test_not_enough_operands_empty_input();
+    test_too_many_operands();
 
     std::cout << "\nTest implementations passed!\n";
 

scripts/file_linter.py

@@ -6,34 +6,44 @@
 with open("git_diff.txt") as in_file:
     modified_files = sorted(in_file.read().splitlines())
     print("{} files were modified.".format(len(modified_files)))
-    
+
     cpp_exts = tuple(".c .c++ .cc .cpp .cu .cuh .cxx .h .h++ .hh .hpp .hxx".split())
     cpp_files = [file for file in modified_files if file.lower().endswith(cpp_exts)]
     print(f"{len(cpp_files)} C++ files were modified.")
     if not cpp_files:
         sys.exit(0)
 
-        subprocess.run(["clang-tidy", "--fix", "-p=build", "--extra-arg=-std=c++11", *cpp_files, "--"], 
-            check=True, text=True, stderr=subprocess.STDOUT)
-
-        subprocess.run(["clang-format", "-i", "-style=file", *cpp_files], 
-            check=True, text=True, stderr=subprocess.STDOUT)
-
-        upper_files = [file for file in cpp_files if file != file.lower()]
-        if upper_files:
-            print(f"{len(upper_files)} files contain uppercase characters:")
-            print("\n".join(upper_files) + "\n")
-
-        space_files = [file for file in cpp_files if " " in file or "-" in file]
-        if space_files:
-            print(f"{len(space_files)} files contain space or dash characters:")
-            print("\n".join(space_files) + "\n")
-
-        nodir_files = [file for file in cpp_files if file.count(os.sep) != 1]
-        if nodir_files:
-            print(f"{len(nodir_files)} files are not in one and only one directory:")
-            print("\n".join(nodir_files) + "\n")
-
-        bad_files = len(upper_files + space_files + nodir_files)
-        if bad_files:
-            sys.exit(bad_files)
+    subprocess.run(
+        [
+            "clang-tidy",
+            "--fix",
+            "-p=build",
+            "--extra-arg=-std=c++11",
+            *cpp_files,
+            "--",
+        ],
+        check=True,
+        text=True,
+        stderr=subprocess.STDOUT,
+    )
+    subprocess.run(
+        ["clang-format", "-i", "-style=file", *cpp_files],
+        check=True,
+        text=True,
+        stderr=subprocess.STDOUT,
+    )
+    upper_files = [file for file in cpp_files if file != file.lower()]
+    if upper_files:
+        print(f"{len(upper_files)} files contain uppercase characters:")
+        print("\n".join(upper_files) + "\n")
+    space_files = [file for file in cpp_files if " " in file or "-" in file]
+    if space_files:
+        print(f"{len(space_files)} files contain space or dash characters:")
+        print("\n".join(space_files) + "\n")
+    nodir_files = [file for file in cpp_files if file.count(os.sep) != 1]
+    if nodir_files:
+        print(f"{len(nodir_files)} files are not in one and only one directory:")
+        print("\n".join(nodir_files) + "\n")
+    bad_files = len(upper_files + space_files + nodir_files)
+    if bad_files:
+        sys.exit(bad_files)