initialise 2d vector in c++

To initialize a 2D vector in C++, you can follow these steps:

1. First, include the necessary header file for working with vectors: cpp #include <vector>

2. Next, declare a variable of type vector<vector<T>>, where T represents the type of elements you want to store in the vector. For example, if you want to store integers, you would use: cpp vector<vector<int>> myVector;

3. To specify the size of the 2D vector, you can use the resize() function. This function takes two arguments: the number of rows and the initial value for each element. For example, if you want a 2D vector with 3 rows and 4 columns, initialized with 0: cpp myVector.resize(3, vector<int>(4, 0));

In this case, myVector will have 3 rows and 4 columns, and all elements will be set to 0.

1. If you want to access or modify specific elements of the 2D vector, you can use the [row][column] syntax. For example, to access the element in the second row and third column: cpp int element = myVector[1][2];

Here, myVector[1] accesses the second row, and myVector[1][2] accesses the third column of that row.

That's it! You have now initialized a 2D vector in C++. Remember to adapt the code to fit your specific needs, such as changing the type of elements or the size of the vector.