leetcode 1027

Author: Pankajcoder1

Codeforces/After Placement/1843A-Sasha and Array Coloring.cpp

@@ -0,0 +1,33 @@
+/*
+    written by Pankaj Kumar.
+    country:-INDIA
+*/
+#include <bits/stdc++.h>
+using namespace std;
+typedef long long ll;
+
+
+int solve(){
+    int n;
+    cin>>n;
+    vector<int> v(n);
+    for(auto &x:v){
+        cin>>x;
+    }
+    sort(v.begin(),v.end());
+    int ans=0;
+    for(int i=0;i<n/2;i++){
+        ans+=(v[n-1-i]-v[i]);
+    }
+    cout<<ans<<endl;
+    return 0;
+}
+int main()
+{
+    int testCase=1;
+    cin>>testCase;
+    while(testCase--){
+        solve();
+    }
+    return 0;
+}

Codeforces/After Placement/1843B-Long Long.cpp

@@ -0,0 +1,49 @@
+/*
+    written by Pankaj Kumar.
+    country:-INDIA
+*/
+#include <bits/stdc++.h>
+using namespace std;
+typedef long long ll;
+
+
+int solve(){
+    int n;
+    cin>>n;
+    long long sum=0;
+    vector<int> v(n);
+    for(auto &x:v){
+        cin>>x;
+        sum += abs(x);
+    }
+    int ans=0;
+    int count=0;
+    for(auto x:v){
+        if(x==0 && count==0){
+            continue;
+        }
+        if(x<=0){
+            count++;
+        }
+        else{
+            if(count>0){
+                ans++;
+            }
+            count=0;
+        }
+    }
+    if(count){
+        ans++;
+    }
+    cout<<sum<<" "<<ans<<endl;
+    return 0;
+}
+int main()
+{
+    int testCase=1;
+    cin>>testCase;
+    while(testCase--){
+        solve();
+    }
+    return 0;
+}

Codeforces/After Placement/1843C-Sum in Binary Tree.cpp

@@ -0,0 +1,29 @@
+/*
+    written by Pankaj Kumar.
+    country:-INDIA
+*/
+#include <bits/stdc++.h>
+using namespace std;
+typedef long long ll;
+
+
+int solve(){
+    long long n;
+    cin>>n;
+    long long sum=0;
+    while(n){
+        sum+=n;
+        n = n/2;
+    }
+    cout<<sum<<endl;
+    return 0;
+}
+int main()
+{
+    int testCase=1;
+    cin>>testCase;
+    while(testCase--){
+        solve();
+    }
+    return 0;
+}

Codeforces/After Placement/1843D-Apple Tree.cpp

@@ -0,0 +1,59 @@
+/*
+    written by Pankaj Kumar.
+    country:-INDIA
+*/
+#include <bits/stdc++.h>
+using namespace std;
+typedef long long ll;
+
+vector<vector<int>> adj;
+vector<int> value;
+
+int dfs(int at, int from){
+    int count=0;
+    for(auto child: adj[at]){
+        if(child!=from){
+            count+=dfs(child,at);
+        }
+    }
+    if(count==0 && adj[at].size()==1){
+        count++;
+    }
+    value[at]=count;
+    return count;
+}
+
+
+int solve(){
+    int n;
+    cin>>n;
+    adj.resize(n+1);
+    value.resize(n+1,0);
+    for(int i=0;i<n-1;i++){
+        int u,v;
+        cin>>u>>v;
+        adj[u].push_back(v);
+        adj[v].push_back(u);
+    }
+    dfs(1,1);
+    int q;
+    cin>>q;
+    for(int i=1;i<=q;i++){
+        int u,v;
+        cin>>u>>v;
+        long long ans=((long long)value[u]*(long long)value[v]);
+        cout<<ans<<endl;
+    }
+    adj.clear();
+    value.clear();
+    return 0;
+}
+int main()
+{
+    int testCase=1;
+    cin>>testCase;
+    while(testCase--){
+        solve();
+    }
+    return 0;
+}

Codeforces/After Placement/682A-Alyona and Numbers.cpp

@@ -0,0 +1,29 @@
+/*
+    written by Pankaj Kumar.
+    country:-INDIA
+*/
+#include <bits/stdc++.h>
+using namespace std;
+typedef long long ll;
+
+
+int solve(){
+    long long n,m;
+    cin>>n>>m;
+    long long ans=0;
+    for(int i=1;i<=n;i++){
+        long long temp=i%5;
+        temp=(m+temp)/5;
+        ans+=temp;
+    }
+    cout<<ans<<endl;
+    return 0;
+}
+int main()
+{
+    int testCase=1;
+    while(testCase--){
+        solve();
+    }
+    return 0;
+}

LeetCode/1027.Longest Arithmetic Subsequence.cpp

@@ -0,0 +1,51 @@
+/*
+    written by Pankaj Kumar.
+    country:-INDIA
+*/
+typedef long long ll;
+const ll INF = 1e18;
+const ll mod1 = 1e9 + 7;
+const ll mod2 = 998244353;
+// Add main code here
+
+class Solution
+{
+public:
+    int longestArithSeqLength(vector<int> &nums)
+    {
+        int n = nums.size();
+        if (n <= 2)
+        {
+            return n;
+        }
+
+        // Create a vector of unordered maps
+        vector<unordered_map<int, int>> dp(n);
+
+        int maxLength = 2;
+
+        for (int i = 0; i < n; i++)
+        {
+            for (int j = 0; j < i; j++)
+            {
+                int diff = nums[i] - nums[j];
+
+                // If the difference exists in the subsequence ending at index j
+                // Extend the subsequence and update the length in dp[i]
+                if (dp[j].find(diff) != dp[j].end())
+                {
+                    dp[i][diff] = dp[j][diff] + 1;
+                }
+                else
+                {
+                    // If the difference doesn't exist, initialize it to 2
+                    dp[i][diff] = 2;
+                }
+
+                maxLength = max(maxLength, dp[i][diff]);
+            }
+        }
+
+        return maxLength;
+    }
+};