session 9-STL.md

1).Address Map

#include<iostream>

#include<map>
using namespace std;

int main()
{
  int n,key_to_deleted=3,a[100],b[100],i,j;
      cin>>n;
  map<int,int>mymap;

    for(i=0;i<n;i++)
    {
        cin>>a[i]>>b[i];
    }
    for(j=0;j<n;j++)
        mymap.insert({a[j],b[j]});
        cin>>key_to_deleted; 
        mymap.erase(key_to_deleted);
  map<int, int>::iterator it1 ;
    for (it1 = mymap.begin(); it1!=mymap.end();  ++it1)
        cout << it1->first << " " << it1->second << endl;
    }

2).Play with Permutations

#include <iostream>

#include <algorithm>

int main()
{
    std::string s;
      std::cin>>s;
    while (1)
    {  
        std::cout << s <<"\n";
        if (!std::next_permutation(s.begin(),s.end()))
        break;
    }

return 0;
}

3).Vector Iterator

#include <iostream>

#include <vector>
#include <iterator>
using namespace std;
int main() {
int num,n;
    cin>>n;
    vector<int>MyVector;
    for(int i=0;i<n;i++)
    {
      cin>>num;
      MyVector.push_back(num);
    }
    vector<int>::iterator ptr;
    for (ptr = MyVector.begin(); ptr < MyVector.end(); ptr++)
          cout << *ptr << " ";
    /*for(int i=0;i<n;i++)
    {
       cout<<MyVector[i]<<" ";
    }*/
    cout<<endl;
    // vector<int>::reverse_iterator;
    vector<int>::reverse_iterator ptr1;
      for (ptr1 = MyVector.rbegin(); ptr1 < MyVector.rend(); ptr1++)
          cout << *ptr1 << " ";
    /* for(int i=n-1;i>=0;i--)
    {
        cout<<MyVector[i]<<" ";
    }*/
    return 0;
  }

4).My Pair

#include <iostream>
#include <utility>
using namespace std;

int main()
{
    pair<int,string>mypair;
    int a;string b;
        cin>>a>>b;
        mypair.first =a;
        mypair.second =b ;

            cout << mypair.first << " " ;
            cout << mypair.second << endl ;

   return 0;
}

5).Remove Duplicate

    #include <iostream>

    #include <list>

    using namespace std;

    int  main() {
    list <int> m;
    int n;
    cin >> n;
    int x;
    for (int i=0; i<n; i++) {
    cin >> x;
     m.push_back(x);
    }
    m.unique();
    for (auto v:m)
    cout << v << " ";
    return 0;
    }

6).Balancing

    #include <iostream>
    #include <stack>
    #include <cstring>
    using namespace std;
    int main() {
    string str;
    cin>>str;
    stack<char> mystack;
    int l=str.size();
    bool flag=true;
    //cout << str << "\n";
    int ref;
    for (int i=0; i<l; i++) {
    if (mystack.size()==0) {
        mystack.push(str[i]);
        continue;
    }
    ref=(int)str[i];
    if (ref>(int)mystack.top()) {
    if (ref-mystack.top() <=2) {
        mystack.pop();
    }
    else {
        cout << "NO\n";
        return 0;
     }
    }
    else {
    mystack.push(str[i]);
    }
    }
    if (mystack.size()==0) {
        cout << "YES\n";
     }
    else {
        cout << "NO\n";
    }
    return 0;
    }

7).Programmer

    #include <iostream>
    #include <vector>
    #include <iterator>
    using namespace std;
    //push_back()
    int main() {
        int num,n;
        cin>>n;
        vector<int> myvector;
        for(int i=0;i<n;i++)
        {
            cin>>num;
            myvector.push_back(num);
        }
        vector<int>::iterator ptr;
        for(ptr=myvector.begin(); ptr<myvector.end();ptr++)
                cout << *ptr <<" ";
                cout<<endl;
        vector<int>::reverse_iterator ptr1;
        for (ptr1=myvector.rbegin();ptr1<myvector.rend();ptr1++)
                cout << *ptr1 <<" ";

        return 0;
        }

8).Sort Game

    #include <bits/stdc++.h>


    using namespace std;

    int main() {
    int n;
    cin >> n;
    int x;
    vector<int>v;
    while(n--) {
    cin >> x;
    v.push_back(x);
    }
    sort(v.begin(), v.end());
    for (auto i:v) {
    cout << i << " ";
    }
    return 0;
    }

9).Vector to Heap

    #include<iostream>

    #include<algorithm>
    #include<vector>
    using namespace std;
    vector<int> myvector;

    int main()
    {
        int n,i;
        cin>>n;
        int input=0; 
        for(i=0;i<n;i++)
        {
            cin>>input;
            myvector.push_back(input);
        }

        make_heap(myvector.begin(), myvector.end());
 
        // Displaying the maximum element of heap
        // using front()

        cout << myvector.front() << endl;
 
        return 0;
    } 

10).Play with Streams

    #include <sstream>
    #include <vector>
    #include <iostream>
    using namespace std;

    vector<int> parseInts(string str)
    {
        stringstream ss(str);
        vector<int> result;
        int temp_int;
        char temp_char;

                ss >> temp_int;
                result.push_back(temp_int);
                while (ss >> temp_char)
                {
                    ss >> temp_int;
                    result.push_back(temp_int);
                 }
                return result;
    }

    int main()
    {
        string str;
        cin >> str;
        vector<int> integers = parseInts(str);
        for (int i = 0; i < integers.size(); i++)
        {
            cout << integers[i] << "\n";
        }

        return 0;
    }

11).Deque

    #include <cstdio>
    #include <deque>
    #include <algorithm>
    #include <iostream>

    using namespace std;

    int a[1000000];
    int x[1000000], y[1000000];
    deque<int> dq2;

    int main()
    {
        int T;
            cin >> T;
            while(T--){
        dq2.clear();
            int n, k;
            scanf("%d %d", &n, &k);

            for (int i = 0; i < n; i++) scanf("%d", a + i);

            for (int i = 0; i < k - 1; i++){

            while (dq2.size() && a[dq2[dq2.size() - 1]] <= a[i]) dq2.pop_back();
                dq2.push_back(i);
         }

        for (int i = 0, j; (j = i + k - 1) < n; i++){
        while (dq2.size() && a[dq2[dq2.size() - 1]] <= a[j]) dq2.pop_back();
        dq2.push_back(j);

        y[i] = a[dq2[0]];
        if (dq2[0] == i) dq2.pop_front();
        }

      for (int i = 0; i <= n - k; i++) printf("%d%c", y[i], i == n - k ? '\n' : ' ');
        }
     return (0);

    }

12).Swapping two Functions

    #include <stack>

    #include <iostream>
    #include <vector>
    #include <bits/stdc++.h>
    using namespace std; 

    int main()
    {
            // stack container declaration
            stack<int> mystack1;
            stack<int> mystack2;  
            vector<int>i;
            vector<int>j;
                int n,k,a;
                    cin>>n;
            for(k=0;k<n;k++)
            {
            cin>>a;
             mystack1.push(a);
     
            }
            for(k=0;k<n;k++)
            {
                 cin>>a;
                mystack2.push(a);
             }

            // using swap() function to swap elements of stacks
             mystack1.swap(mystack2);

            // printing the first stack
            cout<<"";
            while (!mystack1.empty()) {
                cout<<mystack1.top()<<" ";
            mystack1.pop();
        }
        reverse(i.begin(),i.end());
        reverse(j.begin(),j.end());
            // printing the second stack
        cout<<endl;
        while (!mystack2.empty()) {
            cout<<mystack2.top()<<" ";
            mystack2.pop();
    }
    return 0;
}

13).Marks and Vector

    #include <bits/stdc++.h> 
    using namespace std;   
    int main() 
    {
        int input;
        vector<int> myvector; 
        while (cin>>input)
            myvector.push_back(input);
           cout<<*min_element(myvector.begin(),myvector.end())<<" "<<*max_element(myvector.begin(),myvector.end()); 
            return 0; 
    }

14).Play with Set

    #include<bits/stdc++.h>
    #include<iostream>
    #include<set>
    using namespace std;

    int main(){
    set<int>s;
    int size;
    cin >> size;
    int a = size;
    set<int>:: iterator it;
    for(int i = 0; i < size; i++){
    int b;
    cin >> b;
    s.insert(b);
    }
    int c;
    cin >> c;
    if(s.find(c) != s.end()){
    cout << "Element "<< c << " found in the set\n";
    }else{
    cout << "No Element Found\n";
    }
    for(set<int>::iterator itr = s.begin(); itr != s.end(); itr++){
    cout << *itr << " ";
    }
    cout << endl;
    cout << "Size="<< size << endl;
    return 0;
    }

15).Remove Duplicate

    #include <iostream>
    #include <list>

    using namespace std;

    int  main() {
        list <int> m;
        int n;
        cin >> n;
        int x;
        for (int i=0; i<n; i++) {
        cin >> x;
        m.push_back(x);
    }
    m.unique();
    for (auto v:m)
        cout << v << " ";
    return 0;
    }

16).Sets

    #include <iostream>
    #include <set>
    using namespace std;
    int main() {
        int n;
        set<int>s;
        cin >> n;
        while(n--){
   
            int x,y;
            cin >> y >> x;
            if(y == 1){
                    s.insert(x);
            } else if(y == 2){
                     s.erase(x);
            } else {
                    auto itr = s.find(x);
                    if(distance(itr,s.end()) == 0){
                        cout << "No" << endl;
            } else {
                        cout << "Yes" << endl;
            }
        }
    }
    return 0;
}