Finished 21 questions

December 01/c++_dArK-sEiD05_01.cpp

@@ -0,0 +1,19 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+
+int findMissingNumber(int N, vector<int> &array) {
+    int totalSum = N * (N + 1) / 2;
+    int arraySum = 0;
+    for (int num : array) {
+        arraySum += num;
+    }
+    return totalSum - arraySum;
+}
+
+int main() {
+    int N = 5;
+    vector<int> array = {1, 2, 4, 5};
+    cout << findMissingNumber(N, array) << endl;
+    return 0;
+}

December 02/c++_dArK-sEiD05_02.cpp.cpp

@@ -0,0 +1,31 @@
+
+#include <iostream>
+#include <vector>
+using namespace std;
+int main() {
+    // Write C++ code here
+    vector <int> arr= {10, 5, 6, 3, 2, 20, 100}
+;
+
+
+    for (int i = 1; i < arr.size(); i += 2) {
+
+        if(arr[i - 1] < arr[i]) {
+            swap(arr[i - 1], arr[i]);
+        }
+
+        if(i+1<arr.size()&&arr[i]>arr[i + 1]) {
+            swap(arr[i], arr[i + 1]);
+        }
+    }
+
+
+
+    for(int i=0;i<arr.size();i++){
+        cout<<arr[i]<<"\t";
+    }
+
+
+
+    return 0;
+}

December 03/c++_dArK-sEiD05_03.cpp

@@ -0,0 +1,18 @@
+#include <iostream>
+using namespace std;
+int main() {
+
+   int r,b;
+   cout<<"Enter red boxes:";
+   cin>>r;
+   cout<<"Enter blue boxes:";
+   cin>>b;cout<<r<<b<<abs(r-b);
+   if(abs(r-b)==1){
+       cout<<"Not possible";
+   }
+   else{
+       cout<<"Possible";
+   }
+
+    return 0;
+}

December 04/c++_dArK-sEiD05_04.cpp

@@ -0,0 +1,15 @@
+#include <iostream>
+using namespace std;
+
+int main() {
+    int n;
+    cout<<"Enter months:";
+   cin>>n;
+   int i=1;int a=1;int b=1;
+   if(n==1 || n==2){cout<<1;}
+   while(i<=n-2){
+       int c=a+b;a=b;b=c;i++;
+   }
+   cout<<b;
+    return 0;
+}

December 05/c++_dArK-sEiD05_05.cpp

@@ -0,0 +1,20 @@
+
+#include <iostream>
+using namespace std;
+
+int main() {
+
+    int n,k;
+    cout<<"Enter persons:";
+   cin>>n;
+   cout<<"Enter k:";
+   cin>>k;
+   int i=1;int ans=0;
+   while(i<=5){
+       ans=(ans+k)%i;
+       i++;
+   }
+   cout<<ans+1;
+
+    return 0;
+}

December 06/c++_dArK-sEiD05_06.cpp

@@ -0,0 +1,44 @@
+// Online C++ compiler to run C++ program online
+#include <iostream>
+using namespace std;
+#include <vector>
+#include <unordered_map>
+int main() {
+    int n;
+    cout << "Enter the size of the vector: ";
+    cin >> n;
+
+    vector<int> vec(n); 
+    cout<<"Enter target:";
+    int tar;
+    cin>>tar;
+
+    cout << "Enter " << n << " elements: ";
+    for (int i = 0; i < n; i++) {
+        cin >> vec[i];
+    }
+
+    vector<pair<int, int>> pairs;
+    unordered_map<int,int> hm;
+    for(int i=0;i<n;i++){
+        hm[vec[i]]++;
+    }
+    for(int i=0;i<n;i++){
+        if(hm.find((tar-vec[i]))!=0 && hm[abs(vec[i]-tar)]>0){
+            if(vec[i]*2==tar){
+                if(hm[vec[i]]>1){
+                    pairs.push_back({vec[i],(tar-vec[i])});
+                    hm.erase(vec[i]);
+
+                }
+            }else{
+            pairs.push_back({vec[i],(tar-vec[i])});
+            hm[vec[i]]--;hm[vec[i]-tar]--;
+        }}
+    }
+    for (const auto& p : pairs) {
+        cout << "(" << p.first << ", " << p.second << ")" << endl;
+    }
+
+    return 0;
+}

December 07/c++_dArK-sEiD05_07.cpp

@@ -0,0 +1,37 @@
+
+#include <iostream>
+using namespace std;
+#include<vector>
+int main() {
+    int n;
+    cout << "Enter the size of the vector: ";
+    cin >> n;
+    vector<vector<int>> ans;
+    ans.push_back({1});
+    for (int i=1;i<=n;i++){
+        vector<int> temp;
+        int x=0;
+        while(x<=i){
+            int sum=0;
+            if (x < ans[i - 1].size()) {
+                sum += ans[i - 1][x];
+            }
+            if (x - 1 >= 0) {
+                sum += ans[i - 1][x - 1];
+            }
+
+            temp.push_back(sum);x++;
+        }
+        ans.push_back(temp);
+        }
+
+
+    for(int i=0;i<n;i++){
+        for(int j=0;j<ans[i].size();j++){
+            cout<<ans[i][j]<<"\t";
+        }
+        cout<<"\n";
+    }
+
+    return 0;
+}

December 08/c++_dArK-sEiD05_08.cpp

@@ -0,0 +1,22 @@
+// Online C++ compiler to run C++ program online
+#include <iostream>
+using namespace std;
+#include<vector>
+int main() {
+    int n;
+    cout << "Enter the size: ";
+    cin >> n;int i=1;int sum=0;
+    while(i<=n){
+        int k=i;
+        while(k>0){
+            int x=k%10;
+            sum+=x*x;
+            k=k/10;
+        }
+        i++;
+    }
+    cout<<sum;
+
+
+    return 0;
+}

December 09/c++_dArK-sEiD05_09.cpp

@@ -0,0 +1,32 @@
+// Online C++ compiler to run C++ program online
+#include <iostream>
+#include <sstream>
+#include <vector>
+#include <string>
+using namespace std;
+
+
+int main() {
+
+  int n;
+  cout<<"Enter number of elements:";
+  cin>>n;
+  vector<int> vec(n);
+
+  for(int i=0;i<n;i++){
+      cin>>vec[i];
+  }
+  int cnt=0;
+  for(int i=0;i<vec.size();i++){
+      if(vec[i]==1){
+          cnt++;
+      }
+  }
+  cout<<"Occurance"<<cnt;
+
+
+
+
+
+    return 0;
+}

December 10/c++_dArK-sEiD05_10.cpp

@@ -0,0 +1,84 @@
+#include <iostream>
+#include <vector>
+#include <queue>
+#include <unordered_map>
+#include <unordered_set>
+
+using namespace std;
+
+vector<vector<string>> findTaskOrder(const vector<pair<string, vector<string>>> &tasks) {
+    unordered_map<string, vector<string>> graph;
+    unordered_map<string, int> in_degree;
+    unordered_set<string> all_tasks;
+
+    for (const auto &task : tasks) {
+        string current = task.first;
+        all_tasks.insert(current);
+
+        for (const string &dependency : task.second) {
+            graph[dependency].push_back(current);
+            in_degree[current]++;
+            all_tasks.insert(dependency);
+        }
+    }
+
+    queue<string> q;
+    for (const string &task : all_tasks) {
+        if (in_degree[task] == 0) {
+            q.push(task);
+        }
+    }
+
+    vector<vector<string>> result;
+
+    while (!q.empty()) {
+        vector<string> concurrent_tasks;
+        int size = q.size();
+
+        for (int i = 0; i < size; ++i) {
+            string task = q.front();
+            q.pop();
+            concurrent_tasks.push_back(task);
+
+            for (const string &neighbor : graph[task]) {
+                in_degree[neighbor]--;
+                if (in_degree[neighbor] == 0) {
+                    q.push(neighbor);
+                }
+            }
+        }
+
+        result.push_back(concurrent_tasks);
+    }
+
+    for (const auto &entry : in_degree) {
+        if (entry.second > 0) {
+            throw runtime_error("Error: Cyclic dependency detected");
+        }
+    }
+
+    return result;
+}
+
+int main() {
+    vector<pair<string, vector<string>>> tasks = {
+        {"TaskA", {}},
+        {"TaskB", {"TaskA"}},
+        {"TaskC", {"TaskB"}},
+        {"TaskD", {"TaskB", "TaskC"}}
+    };
+
+    try {
+        vector<vector<string>> order = findTaskOrder(tasks);
+        for (const auto &level : order) {
+            for (const string &task : level) {
+                cout << task << " ";
+            }
+            cout << endl;
+        }
+    } catch (const runtime_error &e) {
+        cout << e.what() << endl;
+    }
+
+    return 0;
+}

December 11/c++_dArK-sEiD05_11.cpp

@@ -0,0 +1,29 @@
+#include <iostream>
+#include <string>
+using namespace std;
+
+bool judgeCircle(string moves) {
+    int x = 0, y = 0; 
+    for (char move : moves) {
+        if (move == 'R') x++;    
+        else if (move == 'L') x--; 
+        else if (move == 'U') y++; 
+        else if (move == 'D') y--; 
+    }
+
+    return (x == 0 && y == 0);
+}
+
+int main() {
+    string moves;
+    cout << "Enter the moves: ";
+    cin >> moves;
+
+    if (judgeCircle(moves)) {
+        cout << "The robot returns to the origin." << endl;
+    } else {
+        cout << "The robot does not return to the origin." << endl;
+    }
+
+    return 0;
+}