public class PushAtIndex {

static class Stack{

int maxsize;

int stackArray[];

int top;

Stack(int size){

maxsize= size;

stackArray= new int[size];

top= -1;

}

void push(int val){

if(top==maxsize-1){

System.out.println("Stack overflow");

return;

}

stackArray[++top]= val;

System.out.println(val + " pushed into stack");

}

void pushAtIndex(int index, int val){

if(index<0 || index>top+1){

System.out.println("Invalid index for insertion");

return;

}

if(top==maxsize-1){

System.out.println("Stack overflow");

return;

}

// Shift elements to the right to make space for the new element

for(int i=top; i>=index; i--){

stackArray[i+1]= stackArray[i];

}

stackArray[index]= val;

top++;

System.out.println(val + " inserted at index " + index);

}

void display(){

if(top==-1){

System.out.println("Empty stack");

return;

}

for(int i=0; i<=top; i++){

System.out.print(stackArray[i] + " ");

}

System.out.println();

}

}

public static void main(String[] args) {

Stack st= new Stack(5);

st.push(1);

st.push(2);

st.push(3);

st.push(4);

st.display(); // 1 2 3 4

st.pushAtIndex(2, 98);

st.display(); // 1 2 98 3 4

st.pushAtIndex(3, 16); // Stack overflow

st.pushAtIndex(12, 105); // Invalid index for insertion

}

}