Insert a new value to element of array and move the rest of elements

Question

I am making a program that it will be able to add any numbers on an array and then it will be able to modify them (insert,delete).What I want to know is how to create a new value in an array without modifying anything.Just create the value and push all the rest to the next one.Example: insert 1 8 //insert is just the command,1 is the place where you want to create the new value and 8 is the value itself so list[1] = 8 but I want the rest values that already exist to go 1 forward(if they are in the place I want to create the new value or higher than it(talking about place in the list))

Full example: List:

5
6
7
8
9

Command: insert 3 10 New list:

5
6
7
10 //the one that changed,the rest from this point went 1 forward 
8
9

Answer 1

What you want is to use a std::vector<int> something like this:

std::vector<int> v = {5, 6, 7, 8, 9};
v.insert(v.begin() + 1, 8);   // v[1] now equals 8, everything after push up one
v.erase(v.begin() + 1);       // v is now as it was before above insert
v.insert(v.begin() + 3, 10);  // v[3] is now 10

Answer 2

Let a be the array, position be the index in array where the value has to be inserted, and value be the value itself.

Then try:

int i;
for(i=CURRENT_SIZE_OF_ARRAY-1; i>=positon; --i)
{
   a[i+1] = a[i];
}
a[i]=value;

This way, you shift the array values from the end in order to make space for the new element, and then finally insert that element in the desired location.