очередь в c
#include <queue>
queue<int> q;
q.push(10);
q.push(20);
q.front(); // 10
q.back(); // 20
while (!q.empty())
q.pop();
Vishnu
#include <queue>
queue<int> q;
q.push(10);
q.push(20);
q.front(); // 10
q.back(); // 20
while (!q.empty())
q.pop();#include<iostream>
using namespace std;
class Queue {
private:
int front;
int rear;
int arr[5];
public:
Queue() {
front = -1;
rear = -1;
for (int i = 0; i < 5; i++) {
arr[i] = 0;
}
}
bool isEmpty() {
if (front == -1 && rear == -1)
return true;
else
return false;
}
bool isFull() {
if (rear == 4)
return true;
else
return false;
}
void enqueue(int val) {
if (isFull()) {
cout << "Queue full" << endl;
return;
} else if (isEmpty()) {
rear = 0;
front = 0;
arr[rear] = val;
} else {
rear++;
arr[rear] = val;
}
}
int dequeue() {
int x = 0;
if (isEmpty()) {
cout << "Queue is Empty" << endl;
return x;
} else if (rear == front) {
x = arr[rear];
rear = -1;
front = -1;
return x;
} else {
cout << "front value: " << front << endl;
x = arr[front];
arr[front] = 0;
front++;
return x;
}
}
int count() {
return (rear - front + 1);
}
void display() {
cout << "All values in the Queue are - " << endl;
for (int i = 0; i < 5; i++) {
cout << arr[i] << " ";
}
}
};
int main() {
Queue q1;
int value, option;
do {
cout << "\n\nWhat operation do you want to perform? Select Option number. Enter 0 to exit." << endl;
cout << "1. Enqueue()" << endl;
cout << "2. Dequeue()" << endl;
cout << "3. isEmpty()" << endl;
cout << "4. isFull()" << endl;
cout << "5. count()" << endl;
cout << "6. display()" << endl;
cout << "7. Clear Screen" << endl << endl;
cin >> option;
switch (option) {
case 0:
break;
case 1:
cout << "Enqueue Operation \nEnter an item to Enqueue in the Queue" << endl;
cin >> value;
q1.enqueue(value);
break;
case 2:
cout << "Dequeue Operation \nDequeued Value : " << q1.dequeue() << endl;
break;
case 3:
if (q1.isEmpty())
cout << "Queue is Empty" << endl;
else
cout << "Queue is not Empty" << endl;
break;
case 4:
if (q1.isFull())
cout << "Queue is Full" << endl;
else
cout << "Queue is not Full" << endl;
break;
case 5:
cout << "Count Operation \nCount of items in Queue : " << q1.count() << endl;
break;
case 6:
cout << "Display Function Called - " << endl;
q1.display();
break;
case 7:
system("cls");
break;
default:
cout << "Enter Proper Option number " << endl;
}
} while (option != 0);
return 0;
}// CPP code to illustrate Queue in
// Standard Template Library (STL)
#include <iostream>
#include <queue>
using namespace std;
// Print the queue
void showq(queue<int> gq)
{
queue<int> g = gq;
while (!g.empty()) {
cout << '\t' << g.front();
g.pop();
}
cout << '\n';
}
// Driver Code
int main()
{
queue<int> gquiz;
gquiz.push(10);
gquiz.push(20);
gquiz.push(30);
cout << "The queue gquiz is : ";
showq(gquiz);
cout << "\ngquiz.size() : " << gquiz.size();
cout << "\ngquiz.front() : " << gquiz.front();
cout << "\ngquiz.back() : " << gquiz.back();
cout << "\ngquiz.pop() : ";
gquiz.pop();
showq(gquiz);
return 0;
}#include <queue>
queue<int> gquiz;
gquiz.push(10);
gquiz.push(20);
gquiz.push(30);// C++ program to Print all possible paths from
// top left to bottom right of a mXn matrix
#include<iostream>
using namespace std;
/* mat: Pointer to the starting of mXn matrix
i, j: Current position of the robot (For the first call use 0,0)
m, n: Dimensions of given the matrix
pi: Next index to be filed in path array
*path[0..pi-1]: The path traversed by robot till now (Array to hold the
path need to have space for at least m+n elements) */
void printAllPathsUtil(int *mat, int i, int j, int m, int n, int *path, int pi)
{
// Reached the bottom of the matrix so we are left with
// only option to move right
if (i == 0)
{
for (int k = j; k < n; k++)
path[pi + k - j] = *((mat + i*n) + k);
for (int l = 0; l < (2*n-1); l++)
cout << path[l] << " ";
cout << endl;
return;
}
// Reached the right corner of the matrix we are left with
// only the downward movement.
if (j == n - 1)
{
for (int k = i; k >= m; k--)
path[pi + k + i] = *((mat + k*n) + j);
for (int l = 0; l < (2*n-1); l++)
cout << path[l] << " ";
cout << endl;
return;
}
// Add the current cell to the path being generated
path[pi] = *((mat + i*n) + j);
// Print all the paths that are possible after moving down
printAllPathsUtil(mat, i-1, j, m, n, path, pi + 1);
// Print all the paths that are possible after moving right
printAllPathsUtil(mat, i, j+1, m, n, path, pi + 1);
// Print all the paths that are possible after moving diagonal
// printAllPathsUtil(mat, i+1, j+1, m, n, path, pi + 1);
}
// The main function that prints all paths from top left to bottom right
// in a matrix 'mat' of size mXn
void printAllPaths(int *mat, int m, int n)
{
int *path = new int[m+n];
printAllPathsUtil(mat, m-1, 0, 0, n, path, 0);
}
// Driver program to test above functions
int main()
{
int mat[3][3] = { {1, 2, 3}, {4, 5, 6},{7, 8, 9} };
printAllPaths(*mat, 3, 3);
return 0;
}#include <iostream>
#include <queue>
using namespace std;
int main() {
// create a queue of string
queue<string> animals;
// push elements into the queue
animals.push("Cat");
animals.push("Dog");
cout << "Queue: ";
// print elements of queue
// loop until queue is empty
while(!animals.empty()) {
// print the element
cout << animals.front() << ", ";
// pop element from the queue
animals.pop();
}
cout << endl;
return 0;
}