C++, lambda, map, filter, reduce

main.cpp

//
//  main.cpp
//  tutorial
//
//  Created by king lamar on 10/22/20.
//

#include <iostream>
#include <vector>
#include <random>
#include <ctime>
using namespace std;

std::vector<int> GenerateRandomVect(int numberOfnums, int min, int max);

int main(int argc, const char * argv[]) {
    // sort
    vector<int> vecVals = GenerateRandomVect(10, 1, 1000);
    sort(vecVals.begin(), vecVals.end(), [](int x, int y){ return x < y ;});
    
    for( auto v: vecVals){
        cout << v << " " ;
    }
    cout << endl;
    
    // filter
    vector<int> even;
    copy_if(vecVals.begin(), vecVals.end(),
            back_inserter(even),
            [](int x){return (x % 2 ) == 0;});
    for( auto v: even){
        cout << v << " " ;
    }
    cout << endl;
    
    //map
    int sum = 0;
    for_each(vecVals.begin(), vecVals.end(),
             [&](int x){ sum += x;});
    
    cout << "Sum is " << sum << endl;
    return 0;
}


std::vector<int> GenerateRandomVect(int numberOfnums, int min, int max){
    std::vector<int> vecValues;
    srand(time(NULL));
    int i = 0, randVal = 0;
    while( i < numberOfnums){
        randVal = min + rand() % ((max + 1)) - min;
        vecValues.push_back(randVal);
        i++;
    }
    return vecValues;
}