Category : pass-by-reference

#include<bits/stdc++.h> #include<map> using namespace std; bool greaterThanExists(int i,std::map<int,int>&mpp) { for(auto it:mpp) { if(it.first>i && it.second>0) { cout<<it.first<<endl<<endl; it.second–; return true; } } return false; } int main() { int n; cin>>n; map<int,int>mpp; for(int i=0;i<n;i++) { int x; cin>>x; mpp[x]++; } int i=0; while(greaterThanExists(i,mpp)) i++; // cout<<i<<endl; return 0; } Question:https://codeforces.com/contest/1165/problem/B In this question of Codeforces,I ..

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As highlighted by e.g. this post, matrices can be passed to an arma::mat object by reference: // [[Rcpp::export]] void arma_test_ref( arma::mat& x){} // [[Rcpp::export]] void arma_test_const_ref( const arma::mat& x){} Which other classes foreign to R allow objects to be passed by reference? I am thinking in particular of Armadillo classes like arma::vec, arma::spmat, arma::Mat<int> etc., ..

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I’ve never used std::get_if, and since its name is different from std::get, I don’t see a reason why its argument should be a pointer¹ (whereas std::get has a by-reference parameter). ¹If it was named std::get too, then overload resolution would be a reason enough. Source: Windows Que..

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I want to know what happens if we have a function parameter that is a reference to a const function as shown below. Version 1 int anotherFunc() { std::cout<<"inside anotherFunc"<<std::endl; return 5; } void func(decltype(anotherFunc) const &someFunction)//note the const here { std::cout<<"inside func"<<std::endl; std::cout<<someFunction()<<std::endl; } int main() { std::cout << "Hello World" << std::endl; func(anotherFunc); ..

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Consider following scenario: I need to process fruits which most of the time I get in combinations [but not always, lets assume] so I created enum as shown below : enum class ProcessInputFruits {None, Apples, Mangoes, PineApples, Grapes, GrapesAndMangoes, ApplesAndPineApples, All}; In my function ProcessFruits I am passing this enum as argument but at the ..

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I have a legacy interface that has a function with a signature that looks like the following: int provide_values(int &x, int &y) x and y are considered output parameters in this function. Note: I’m aware of the drawbacks of using output parameters and that there are better design choices for such an interface. I’m not ..

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