1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 | #include<iostream.h> #include<conio.h> int front=0,rear=0; //initializing varible for needed operations in queue. int flag=0; int i,size; int q[10]; class qu { public: void insert() //Function to insert elements into queue. { if(rear>=size) //insertion is not possible if rear met to its maximum size of queue, { cout<<"QUEUE IS FULL\n"; } //element can be inserted if rear less than size of queue else { rear++; //increment rear by 1. cout<<"ENTER ELEMENT TO ADD\n"; cin>>q[rear]; //element is stored on q[rear] and rear vlue is incremented by 1 for each insertion until rear become equal to size. } } void dele() // function to deletion is possible only if there is atlest 1 element in queue. that is rear>0. { if(rear>0) { front++; q[front]=NULL; for(i=1;i<=rear;i++) { q[i]=q[i+1]; //deletion of an front element in queue will leads to a NULL value in front so rewrite all the element back to avoid NULL space. } rear--; //decrement rear by 1. front--; //decrement front by 1. } else { cout<<"QUEUE IS EMPTY\n"; } } void display() //function to disply element in the queue. { if(rear>0) { for(i=1;i<=rear;i++) { cout<<q[i]<<","; } } else { cout<<"QUEUE IS EMPTY\n"; } } }; void main() { int ch; qu s; if(flag==0) { clrscr(); cout<<"ENTER ARRAY SIZE\n"; //recieve size of queue from user. cin>>size; flag=1; } cout<<"\n\n1:INSERT\n2:DELETE\n3:DISPLAY\n"; cin>>ch; switch(ch) //choice for user to select their function to insert,delete and display { case 1 : s.insert(); main(); break; case 2 : s.dele(); main(); break; case 3 : s.display(); main(); break; default : cout<<"INVALID KEY VALUE\n"; break; } getch(); } |
