The operationalresearchapp from treborsky

Updating elements of a std::vector that is a public member of a class

In the snipper below, I encountered a problem, where I can't update the std::vector element or add new ones. I don't think it's because of the new C++20. The compiler error is as follows:
__ function 'operator[]' which returns const-qualified type 'std::vector::const_reference' (aka 'const Ingredient &') declared here __
__ candidate function template not viable: 'this' argument has type 'const std::vector', but method is not marked const __

OperationalResearchApp/model/src/model/model.cpp

Lines 25 to 87 in 824eab0

 double Solution::calculateMshop() const { 

 double Mshop = 0.0; 

 for(std::size_t j = 0; j < selectedRecipes.size(); ++j) { 

 // determine if we have all ingredients for the recipe 

 // if we don't have enough amount of an ingredient, then we buy one (we add the cost and increase 

 // the ingredient amount) 

 if (selectedRecipes[j]) { // we select availableRecipies[i] 

 for(std::size_t i = 0; i < appData.availableRecipies[i].ingredientList.size(); ++i) { 

 // search through the ingredient list and determine if we have enough of the ingredient 

 Ingredient currentRecipeIngredient = appData.availableRecipies[j].ingredientList[i]; 

 std::size_t idxIfWeHaveIt = -1; 

 bool isEnough = false; 

 for(std::size_t k = 0; k < appData.storedIngredients.size(); ++k) { 

 if (appData.storedIngredients[k].name == currentRecipeIngredient.name) { // do we have it on the list 

 idxIfWeHaveIt = k; 

 if (appData.storedIngredients[k].amount >= currentRecipeIngredient.amount) { // do we have enough of the thing 

 isEnough = true; // we have enough of the thing do make the recipe 

 break; 

 } 

 break; 

 } 

 } 

 if (!isEnough) { // then we have to buy it 

 for(std::size_t k = 0; k < appData.shopSupplies.size(); ++k) { // we want to find a supply with the same name 

 if (appData.shopSupplies[k].name == currentRecipeIngredient.name) { // if we found it, we buy it 

 Mshop += (double)appData.shopSupplies[k].price; // we buy it 

 // TODO: include the Money variable from the mathematical model, right now we have 

 // basically infinite resources 

 if (idxIfWeHaveIt != -1) { 

 appData.storedIngredients[idxIfWeHaveIt].amount += appData.shopSupplies[k].amount; // TODO: fix this stuff 

 // because of C++20, we have to rewrite the entire vector of ingredients to update one element -> wtf 

 int expDate = appData.storedIngredients[idxIfWeHaveIt].expirationDate; 

 int amount = appData.storedIngredients[idxIfWeHaveIt].amount; 

 std::string name = appData.storedIngredients[idxIfWeHaveIt].name; 

 Ingredient updatedIngredient(expDate, amount + appData.shopSupplies[k].amount, name); 

 std::vector<Ingredient> newStoredIngredients; 

 newStoredIngredients.reserve(appData.storedIngredients.size()); 

 for(std::size_t l = 0; l < appData.storedIngredients.size(); ++l) { 

 if (l != idxIfWeHaveIt) { 

 newStoredIngredients.push_back(appData.storedIngredients[l]); 

 } else { 

 newStoredIngredients.push_back(updatedIngredient); 

 } 

 } // we bought it goddamit, we also updated the vector 

 } else { // if we didn't have it in the first place 

 int expDate = appData.storedIngredients[k].expirationDate; 

 int amount = appData.storedIngredients[k].amount; 

 std::string name = appData.storedIngredients[k].name; 

 appData.storedIngredients.emplace_back(Ingredient(expDate, amount, name)); 

 } 

 break; 

 } 

 } 

 } 

 } 

 } 

 } 

 return 0.0; 

 }

Multiplatform file parsing

nlohmann's json parser seems to work only on unix systems (Ubuntu 18.04 tested). We need windows compatibility, so we need to implement some sort of conversion that gets this done. We can do it in two ways:

Algorythm (function)
Input: windows formatted or linux formatted .json file
Output: linux formatted .json file
This is a bad idea, because the linux binary won't get a windows file
Preprocessor logic
If we add proper logic to our code, it will compile different parser versions for linux and windows builds.
I think it's the better idea tbh.

treborsky / operationalresearchapp Goto Github PK

operationalresearchapp's People

Contributors

Stargazers

Watchers

operationalresearchapp's Issues

Updating elements of a std::vector that is a public member of a class

Multiplatform file parsing

Parsing strings into std::size_t and std::string

Implement solution space generation

Implement data structures and model

Implement Tabu Search algorythm

Recommend Projects

React

Vue.js

Typescript

TensorFlow

Django

Laravel

D3

Recommend Topics

javascript

web

server

Machine learning

Visualization

Game

Recommend Org

Facebook

Microsoft

Google

Alibaba

D3

Tencent

	double Solution::calculateMshop() const {
	double Mshop = 0.0;
	for(std::size_t j = 0; j < selectedRecipes.size(); ++j) {
	// determine if we have all ingredients for the recipe
	// if we don't have enough amount of an ingredient, then we buy one (we add the cost and increase
	// the ingredient amount)
	if (selectedRecipes[j]) { // we select availableRecipies[i]
	for(std::size_t i = 0; i < appData.availableRecipies[i].ingredientList.size(); ++i) {
	// search through the ingredient list and determine if we have enough of the ingredient
	Ingredient currentRecipeIngredient = appData.availableRecipies[j].ingredientList[i];
	std::size_t idxIfWeHaveIt = -1;
	bool isEnough = false;
	for(std::size_t k = 0; k < appData.storedIngredients.size(); ++k) {
	if (appData.storedIngredients[k].name == currentRecipeIngredient.name) { // do we have it on the list
	idxIfWeHaveIt = k;
	if (appData.storedIngredients[k].amount >= currentRecipeIngredient.amount) { // do we have enough of the thing
	isEnough = true; // we have enough of the thing do make the recipe
	break;
	}
	break;
	}
	}
	if (!isEnough) { // then we have to buy it
	for(std::size_t k = 0; k < appData.shopSupplies.size(); ++k) { // we want to find a supply with the same name
	if (appData.shopSupplies[k].name == currentRecipeIngredient.name) { // if we found it, we buy it
	Mshop += (double)appData.shopSupplies[k].price; // we buy it
	// TODO: include the Money variable from the mathematical model, right now we have
	// basically infinite resources
	if (idxIfWeHaveIt != -1) {
	appData.storedIngredients[idxIfWeHaveIt].amount += appData.shopSupplies[k].amount; // TODO: fix this stuff
	// because of C++20, we have to rewrite the entire vector of ingredients to update one element -> wtf
	int expDate = appData.storedIngredients[idxIfWeHaveIt].expirationDate;
	int amount = appData.storedIngredients[idxIfWeHaveIt].amount;
	std::string name = appData.storedIngredients[idxIfWeHaveIt].name;

	Ingredient updatedIngredient(expDate, amount + appData.shopSupplies[k].amount, name);

	std::vector<Ingredient> newStoredIngredients;
	newStoredIngredients.reserve(appData.storedIngredients.size());

	for(std::size_t l = 0; l < appData.storedIngredients.size(); ++l) {
	if (l != idxIfWeHaveIt) {
	newStoredIngredients.push_back(appData.storedIngredients[l]);
	} else {
	newStoredIngredients.push_back(updatedIngredient);
	}
	} // we bought it goddamit, we also updated the vector

	} else { // if we didn't have it in the first place
	int expDate = appData.storedIngredients[k].expirationDate;
	int amount = appData.storedIngredients[k].amount;
	std::string name = appData.storedIngredients[k].name;
	appData.storedIngredients.emplace_back(Ingredient(expDate, amount, name));
	}
	break;
	}
	}
	}
	}
	}
	}
	return 0.0;
	}