Array Questions Part — 3(CPP)
Why is Melody so chocolaty?
Why is Melody so chocolaty? | Practice | GeeksforGeeks
Chunky gets happy by eating Melody. Given an array of N elements, each element represents happiness chunky get by…
int max_adjacent_sum(int arr[], int n)
{
// Complete the function
int max = arr[0] + arr[1];
for(int i=1;i<n-1;i++)
{
if(max < (arr[i]+ arr[i+1]))
max = arr[i] + arr[i+1];
}
return max;
}
Sum of distinct elements
Sum of distinct elements | Practice | GeeksforGeeks
You are given an array Arr of size N. Find the sum of distinct elements in an array. Example 1: Input: N = 5 Arr[] =…
class Solution{
public:
// Find the sum of all non-repeated elements
// in an array
int findSum(int arr[], int n) {
// code here
sort(arr, arr+n);
int sum = 0;
for (int i=0;i<n;i++)
{
if (arr[i] != arr[i+1])
sum += arr[i];
}
return sum;
}
};
Using Unordered_map STL
class Solution{
public:
// Find the sum of all non-repeated elements
// in an array
int findSum(int arr[], int n) {
// code here
unordered_map<int, int> m1;
int sum=0;
for(int i=0;i<n;i++)
{
auto search =m1.find(arr[i]);
if ( search != m1.end())
m1[arr[i]]++;
else
m1[arr[i]] = 1;
}
for(auto i : m1)
sum += i.first;
return sum;
}
};
Using set STL
class Solution{
public:
// Find the sum of all non-repeated elements
// in an array
int findSum(int arr[], int n) {
set<int>s;
for(int i=0;i<n;i++)
{
s.insert(arr[i]);
}
return accumulate(s.begin(),s.end(),0);
}
};
Value equal to index value
Value equal to index value | Practice | GeeksforGeeks
Given an array arr. Your task is to find the elements whose value is equal to that of its index value ( Consider…
class Solution{
public:
vector<int> valueEqualToIndex(int arr[], int n) {
// code here
vector<int> temp;
for(int i=0;i<n;i++)
{
if( i+1 == arr[i])
temp.push_back(arr[i]);
}
return temp;
}
};
Missing number in shuffled array
Missing number in shuffled array | Practice | GeeksforGeeks
Given an array A of size N. The contents of A are copied into another array B and numbers are shuffled. Also, one…
class Solution{
public:
long long findMissing(long long a[], long long b[], int n)
{
long long int sum = 0 ;
for(int i=0;i<n;i++)
sum += a[i];
for(int i=0;i<n-1;i++)
sum -= b[i];
return sum;
}
};
Check Equal Arrays
Check Equal Arrays | Practice | GeeksforGeeks
Given two arrays arr1 and arr2 of equal size, the task is to find whether the given arrays are equal. Two arrays are…
class Solution{
public:
//Function to check if two arrays are equal or not.
bool check(vector<ll> A, vector<ll> B, int N) {
//code here
if (A.size()== B.size())
{
sort(A.begin(), A.end());
sort(B.begin(), B.end());
for(int i=0;i<A.size();i++)
{
if(A.at(i)!= B.at(i))
{
return 0;
}
}
return 1;
}
return 0;
}
};
Binary Array Sorting
Binary Array Sorting | Practice | GeeksforGeeks
Given a binary array A[] of size N. The task is to arrange the array in increasing order. Note: The binary array…
class Solution{
public:
// A[]: input array
// N: input array
//Function to sort the binary array.
void binSort(int arr[], int N)
{
//Your code here
int c0=0, c1=0;
for(int i=0;i<N;i++){
if(arr[i] == 0)
c0++;
else if(arr[i]==1)
c1++;
}
for(int i=0;i<c0;i++)
arr[i] =0;
for(int i=c0;i<c0+c1;i++)
arr[i] =1;
}
};
Binary Search
Binary Search | Practice | GeeksforGeeks
Given a sorted array arr and an integer k, find the position(0-based indexing) at which k is present in the array using…
class Solution {
public:
int binarysearch(int arr[], int n, int k) {
// code here
int i =0, j = n-1;
int m;
while(i<=j)
{
m=(i+j)/2;
if(arr[m] == k)
return m;
else if(arr[m] > k)
j= m-1;
else
i = m+1;
}
return -1;
}
};
Peak element
Peak element | Practice | GeeksforGeeks
Given an 0-indexed array of integers arr[] of size n, find its peak element and return it's index. An element is…
class Solution
{
public:
int peakElement(int arr[], int n)
{
int s, e, m;
s=0;
e = n-1;
while(s<e)
{
m = s +(e-s)/2;
if (arr[m] > arr[m+1])
e=m;
else
s = m+1;
}
return s;
}
};
or
int peakElement(int arr[], int n)
{
// Your code here
int result=0 ;
for(int i=0;i<n-1;i++)
if (arr[i+1] > arr[i])
result = i+1;
return result;
}
Array Search
Array Search | Practice | GeeksforGeeks
Given an array, arr of n integers, and an integer element x, find whether element x is present in the array. Return the…
class Solution {
public:
// Function to search x in arr
// arr: input array
// X: element to be searched for
int search(vector<int>& arr, int x) {
// Your code here
for(int i=0;i<arr.size(); i++)
if( arr[i] == x)
return i;
return -1;
}
};
Array Subset
Array Subset | Practice | GeeksforGeeks
Given two arrays: a1[0..n-1] of size n and a2[0..m-1] of size m, where both arrays may contain duplicate elements. The…
string isSubset(int a1[], int a2[], int n, int m) {
map<int, int> freq;
for(int i=0;i<n;i++)
freq[a1[i]]++;
for(int i=0;i<m;i++)
{
if(freq[a2[i]] > 0)
freq[a2[i]]--;
else
return "No";
}
return "Yes";
}
Reverse array in groups
Reverse array in groups | Practice | GeeksforGeeks
Given an array arr of positive integers. Reverse every sub-array group of size k. Note: If at any instance, k is…
class Solution{
public:
//Function to reverse every sub-array group of size k.
void reverseInGroups(vector<long long>& arr, int n, int k){
// code here
int i;
for(int i =0;i<n;i+=k)
{
if(i+k>n)
reverse(arr.begin()+i, arr.end());
else
reverse(arr.begin()+i, arr.begin()+i+k);
}
}
};