I have just started learning C++ and i want to know how i can append values to an array.
say I have to append the squares of first N natural numbers, in python i would do
for i in range(N):
arr.append(i**k)
how do i do this in C++?
i know i’ll first define
int arr[n];
and also for raised to power i will use
pow(i,2);
Array is static size fixed u will have to use vector
you can use dynamic arrays in C++
example
vector<int> arr;
this will declare a dynamic array named arr, in order to insert something in this array you will have to use push_back() function
arr.push_back(1);
arr.push_back(2);
arr.push_back(3);
arr.push_back(4);
now array will contain 4 elements [1, 2, 3, 4]
similarly to insert square of natural number you can do the following
vector<int> arr;
for(int i = 1; i <= N; i++) {
arr.push_back(pow(i, 2));
}
for more information about vectors refer to std::vector - cppreference.com
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thanks a ton!!!
either use STL vector or list.
c++ stl list has many functions like push_back(),pop_back(),push_front(),pop_front(),reverse() etc.most of operations on python list can be done here in c++ list
cannot convert ‘std::vector’ to ‘int*’ for argument ‘1’
how to fix this error?
can you share the code?
prog.cpp: In function ‘int main()’:
prog.cpp:46:25: error: cannot convert ‘std::vector<int>’ to ‘int*’ for argument ‘1’ to ‘int findbit(int*, int, int)’
findbit(list_,n,sum);
this is the error…i would prefer not to share code if possible 
If your talking about inserting elements in an array then you can simply use a for loop
for(int i;i<n;i++)
{
cin>>a[i];
}
not taken as input…
it seems like you are passing a std::vector to an int*
you should change your function header int findbit(int*, int, int) to int findbit(std::vector<int>, int, int)
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Ok change int* to vector<int>&. Next problem is do not use pow to compute integer values, it is not meant for that. Use 1<<k instead.
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