Hello Friends,
#include<stdio.h> #include<stdlib.h> struct stack { int data; struct stack *next; }; struct stack *top = NULL; struct stack *getNode() { return (struct stack*)malloc(sizeof(struct stack)); } void push() { int val; struct stack *newnode; printf("\n Enter data :"); scanf("%d",&val); newnode = getNode(); newnode->data = val; if(top == NULL) { top = newnode; newnode->next = NULL; } else { newnode->next = top; top = newnode; } } void pop() { int x; struct stack *del,*temp; temp = top; if(temp== NULL) printf("\n stack underflow"); else { x=temp->data; top = temp->next; free(temp); printf("\n Deleted element is %d",x); } } void peek() { if(top == NULL) printf("\n Stack Underflow"); else { printf("Peek value : %d \n ",top->data); } } void disp() { struct stack *temp=top; if(top == NULL) printf("\n Stack underflow \n"); else { printf("\n Stack elements are : "); while(temp!=NULL) { printf("%d \t",temp->data); temp = temp->next; } } } void quit() { printf("\n Thank you!!! \n\n"); } void main() { int ch; do{ printf("\n == MENU =="); printf("\n 1. PUSH "); printf("\n 2. POP "); printf("\n 3. PEEK "); printf("\n 4. DISPLAY "); printf("\n 5. QUIT"); printf("\n Enter your choice :"); scanf("%d",&ch); switch(ch) { case 1 : push(); break; case 2 : pop(); break; case 3 : peek(); break; case 4 : disp(); break; case 5 : quit(); break; default : printf("\n Invalid input"); } }while(ch!=5); } /* OUTPUT : == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :1 Enter data :50 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :1 Enter data :20 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :1 Enter data :30 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :1 Enter data :40 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :1 Enter data :10 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :4 Stack elements are : 10 40 30 20 50 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :3 Peek value : 10 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :2 Deleted element is 10 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :4 Stack elements are : 40 30 20 50 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :2 Deleted element is 40 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :2 Deleted element is 30 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :4 Stack elements are : 20 50 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :2 Deleted element is 20 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :3 Peek value : 50 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :4 Stack elements are : 50 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :3 Peek value : 50 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :2 Deleted element is 50 == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :3 Stack Underflow == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :4 Stack underflow == MENU == 1. PUSH 2. POP 3. PEEK 4. DISPLAY 5. QUIT Enter your choice :5 Thank you!!! */
