#include <stdio.h> #include <stdlib.h> #define MAX_SIZE 100 // Define the structure for the queue struct Queue { int arr[MAX_SIZE]; int front, rear; }; // Function to initialize a queue void initialize(struct Queue *queue) { queue->front = -1; queue->rear = -1; } // Function to check if the queue is empty int isEmpty(struct Queue *queue) { return queue->front == -1; } // Function to check if the queue is full int isFull(struct Queue *queue) { return (queue->rear + 1) % MAX_SIZE == queue->front; } // Function to enqueue an element into the queue void enqueue(struct Queue *queue, int value) { if (isFull(queue)) { printf("Queue overflow: Cannot enqueue element %d\n", value); return; } if (isEmpty(queue)) { queue->front = 0; } queue->rear = (queue->rear + 1) % MAX_SIZE; queue->arr[queue->rear] = value; } // Function to dequeue an element from the queue int dequeue(struct Queue *queue) { if (isEmpty(queue)) { printf("Queue underflow: Cannot dequeue element\n"); return -1; } int value = queue->arr[queue->front]; if (queue->front == queue->rear) { queue->front = -1; queue->rear = -1; } else { queue->front = (queue->front + 1) % MAX_SIZE; } return value; } // Function to display the elements in the queue void display(struct Queue *queue) { if (isEmpty(queue)) { printf("Queue is empty\n"); return; } int current = queue->front; printf("Queue elements: "); while (current != queue->rear) { printf("%d ", queue->arr[current]); current = (current + 1) % MAX_SIZE; } printf("%d\n", queue->arr[current]); } int main() { struct Queue queue; initialize(&queue); // Enqueue elements enqueue(&queue, 10); enqueue(&queue, 20); enqueue(&queue, 30); // Display queue display(&queue); // Dequeue elements printf("Dequeued element: %d\n", dequeue(&queue)); printf("Dequeued element: %d\n", dequeue(&queue)); // Display queue after dequeue display(&queue); return 0; }
Write, Run & Share C Language code online using OneCompiler's C online compiler for free. It's one of the robust, feature-rich online compilers for C language, running the latest C version which is C18. Getting started with the OneCompiler's C editor is really simple and pretty fast. The editor shows sample boilerplate code when you choose language as 'C' and start coding!
OneCompiler's C online editor supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample C program which takes name as input and print your name with hello.
#include <stdio.h>
int main()
{
char name[50];
printf("Enter name:");
scanf("%s", name);
printf("Hello %s \n" , name );
return 0;
}
C language is one of the most popular general-purpose programming language developed by Dennis Ritchie at Bell laboratories for UNIX operating system. The initial release of C Language was in the year 1972. Most of the desktop operating systems are written in C Language.
When ever you want to perform a set of operations based on a condition if-else
is used.
if(conditional-expression) {
// code
} else {
// code
}
You can also use if-else for nested Ifs and if-else-if ladder when multiple conditions are to be performed on a single variable.
Switch is an alternative to if-else-if ladder.
switch(conditional-expression) {
case value1:
// code
break; // optional
case value2:
// code
break; // optional
...
default:
// code to be executed when all the above cases are not matched;
}
For loop is used to iterate a set of statements based on a condition.
for(Initialization; Condition; Increment/decrement){
// code
}
While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.
while(condition) {
// code
}
Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.
do {
// code
} while (condition);
Array is a collection of similar data which is stored in continuous memory addresses. Array values can be fetched using index. Index starts from 0 to size-1.
data-type array-name[size];
data-type array-name[size][size];
Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity.
Two types of functions are present in C
Library functions are the in-built functions which are declared in header files like printf(),scanf(),puts(),gets() etc.,
User defined functions are the ones which are written by the programmer based on the requirement.
return_type function_name(parameters);
function_name (parameters)
return_type function_name(parameters) {
//code
}