I would like to know if there are ways to simplify the for loop, such as a lambda expression without changing the nature of the code below. If possible, I would also like to know if there are other ways(better) to execute a series of functions that could do something similarly like the code below. Thank you
#include <iostream>
#include <functional>
#include <vector>
using namespace std;
void turn_left(){ // left turn function
cout<<"Turn left"<<endl;
}
void turn_right(){ // right turn function
cout<<"Turn right"<<endl;
}
void onward(){ // moving forward function
cout<<"Onward"<<endl;
}
int main() {
vector<char>commands{'L', 'R', 'M'}; // commmands (keys)for robot to turn or move;
vector<pair<function<void()>, char>> actions; // a vector of pairs, which pairs up the function pointers with the chars;
actions.push_back(make_pair(turn_left, 'L')); //populate the vector actions
actions.push_back(make_pair(turn_right, 'R'));
actions.push_back(make_pair(onward, 'M'));
for (int i =0; i<commands.size();++i){
if(commands.at(i)==actions.at(i).second){
actions.at(i).first();
}
}
}
Instead of using a lambda to make the code simpler you can use a std::map
/ std::unordered_map
to map a function to a command and then you can simply use a ranged based for loop it iterate through all of the commands you have.
int main() {
vector<char>commands{'L', 'R', 'M'}; // commmands (keys)for robot to turn or move;
std::map<char, function<void()>> actions = {{'L', turn_left},{'R', turn_right},{'M', onward}};
for (auto command : commands)
actions[command]();
}
I would add a function to execute a command then call that from the loop:
#include <iostream>
#include <functional>
#include <vector>
using namespace std;
void turn_left(){ // left turn function
cout<<"Turn left"<<endl;
}
void turn_right(){ // right turn function
cout<<"Turn right"<<endl;
}
void onward(){ // moving forward function
cout<<"Onward"<<endl;
}
// The next step is to put actions/executeAction() into a class.
vector<pair<char, function<void()>>> actions; // a vector of pairs, which pairs up the function pointers with the chars;
void executeAction(char command)
{
auto find = actions.find(command);
if (find != actions.end()) {
find->second();
}
}
int main() {
vector<char>commands{'L', 'R', 'M'}; // commmands (keys)for robot to turn or move;
actions.push_back(make_pair('L', turn_left)); //populate the vector actions
actions.push_back(make_pair('R', turn_right));
actions.push_back(make_pair('M', onward));
for (auto c: commands){
executeAction(c);
}
}
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