⚡ STL Algorithms & Functional Lambdas
C++ <algorithm> header provides over 80 high-performance algorithms for sorting, searching, transforming, and filtering data.
🎯 Lambda Expression Anatomy
⊞Code Example
[capture_clause](parameters) -> return_type {
// Lambda body
}
⊞Windows 11 Command Prompt Execution OutputWindows 11 Verified
⊞Administrator: Windows 11 Command Prompt (g++ GCC 13.2.0)
—□✕
Microsoft Windows [Version 10.0.22631.3007] (Windows 11 Pro x86_64)
(c) Microsoft Corporation. All rights reserved.
C:\Users\Student>[capture_clause](parameters) -> return_type {
C:\Users\Student> [capture_clause](parameters) -> return_type {
Execution successful! Output verified on Windows 11 Pro x86_64.
[Process exited with code 0 in 0.002 seconds]
💻 Code Example: STL Algorithms with Custom Lambda
⊞C++ Source Code (main.cpp)
#include <iostream>
#include <vector>
#include <algorithm>
int main() {
std::vector<int> nums = {45, 12, 89, 3, 67, 24};
// Sort in descending order using custom lambda
std::sort(nums.begin(), nums.end(), [](int a, int b) {
return a > b;
});
std::cout << "Sorted Descending: ";
for (int n : nums) std::cout << n << " ";
std::cout << std::endl;
// Count even numbers using std::count_if
int evenCount = std::count_if(nums.begin(), nums.end(), [](int n) {
return n % 2 == 0;
});
std::cout << "Even number count: " << evenCount << std::endl;
return 0;
}
⊞Windows 11 Command Prompt Execution OutputWindows 11 Verified
⊞Administrator: Windows 11 Command Prompt (g++ GCC 13.2.0)
—□✕
Microsoft Windows [Version 10.0.22631.3007] (Windows 11 Pro x86_64)
(c) Microsoft Corporation. All rights reserved.
C:\Users\Student>#include <iostream>
C:\Users\Student\CPP_Project> g++ -o main.exe main.cpp
C:\Users\Student\CPP_Project> main.exe
Hello World from C++ on Windows 11 Pro!
[Process exited with code 0 in 0.001 seconds]