From 6c6328375c55683645146909b7ab760d0de0d463 Mon Sep 17 00:00:00 2001 From: Santo Cariotti Date: Sun, 18 Oct 2020 18:56:43 +0200 Subject: chore: name of first year folder --- 1_anno/Programmazione_2/exercises/pop-stack.cc | 132 +++++++++++++++++++++++++ 1 file changed, 132 insertions(+) create mode 100644 1_anno/Programmazione_2/exercises/pop-stack.cc (limited to '1_anno/Programmazione_2/exercises/pop-stack.cc') diff --git a/1_anno/Programmazione_2/exercises/pop-stack.cc b/1_anno/Programmazione_2/exercises/pop-stack.cc new file mode 100644 index 0000000..3739450 --- /dev/null +++ b/1_anno/Programmazione_2/exercises/pop-stack.cc @@ -0,0 +1,132 @@ +#include +#include + +using namespace std; + +template +class node { +public: + node(T key, node* next) : _key{key}, _next{next} {} + node(T key) : _key{key}, _next{nullptr} {} + const T& key() const { return _key; } + T& key() { return _key; } + const node*& next() const { return _next; } + node*& next() { return _next; } +private: + T _key; + node* _next; +}; + +template +class Pila { +public: + Pila() : _head{nullptr}{} + ~Pila() { + + } + Pila* push(T val) { + if(!_head) { + _head = new node{val, nullptr}; + } else { + _head = new node{val, _head}; + } + + return this; + } + node* pop() { + if(!_head) return nullptr; + node* elem = _head; + delete _head; + _head = elem->next(); + + return elem; + } + + bool is_empty() { return _head == nullptr; } +private: + node* _head; +}; + +int main() { + ifstream in("input.txt"); + ofstream out("output.txt"); + + for(int ts = 0; ts < 100; ++ts) { + string t; + int n; + in >> t; + switch(t.at(0)) { + case 'b': { + Pila* stack = new Pila{}; + in >> n; + string s; + for(int i = 0; i < n; ++i) { + in >> s; + if(s.at(0) == 'i') { + stack->push(s.at(1) - '0'); + } else { + stack->pop(); + } + } + while(!stack->is_empty()) + out << stack->pop()->key() << ' '; + out << endl; + break; + } + case 'd': { + Pila* stack = new Pila{}; + in >> n; + string s; + for(int i = 0; i < n; ++i) { + in >> s; + if(s.at(0) == 'i') { + stack->push(stod(s.substr(1, s.length()-1))); + } else { + stack->pop(); + } + } + while(!stack->is_empty()) + out << stack->pop()->key() << ' '; + out << endl; + break; + } + case 'c': { + Pila* stack = new Pila{}; + in >> n; + string s; + for(int i = 0; i < n; ++i) { + in >> s; + if(s.at(0) == 'i') { + stack->push(s.at(1)); + } else { + stack->pop(); + } + } + while(!stack->is_empty()) + out << stack->pop()->key() << ' '; + out << endl; + break; + } + case 'i': { + Pila* stack = new Pila{}; + in >> n; + string s; + for(int i = 0; i < n; ++i) { + in >> s; + if(s.at(0) == 'i') { + stack->push(stoi(s.substr(1, s.length()-1))); + } else { + stack->pop(); + } + } + while(!stack->is_empty()) + out << stack->pop()->key() << ' '; + out << endl; + break; + } + } + } + in.close(); + out.close(); + return 0; +} -- cgit v1.2.3-18-g5258