C ++程序在STL中实现队列
队列是遵循先进先出(FIFO)顺序的线性结构，在该顺序中，对队列的元素执行操作。
算法
Functions used here: q.size() = Returns the size of queue. q.push() = It is used to insert elements to the queue. q.pop() = To pop out the value from the queue. q.front() = Returns the front element of the array. q.back() = Returns the back element of the array.
范例程式码
#include<iostream>
#include <queue>
#include <string>
#include <cstdlib>
using namespace std;
int main() {
queue<int> q;
int c, i;
while (1) {
cout<<"1.Size of the Queue"<<endl;
cout<<"2.Insert Element into the Queue"<<endl;
cout<<"3.Delete Element from the Queue"<<endl;
cout<<"4.Front Element of the Queue"<<endl;
cout<<"5.Last Element of the Queue"<<endl;
cout<<"6.Exit"<<endl;
cout<<"Enter your Choice: ";
cin>>c;
switch(c) {
case 1:
cout<<"Size of the Queue: ";
cout<<q.size()<<endl;
break;
case 2:
cout<<"Enter value to be inserted: ";
cin>>i;
q.push(i);
break;
case 3:
i = q.front();
q.pop();
cout<<"Element "<<i<<" Deleted"<<endl;
break;
case 4:
cout<<"Front Element of the Queue: ";
cout<<q.front()<<endl;
break;
case 5:
cout<<"Back Element of the Queue: ";
cout<<q.back()<<endl;
break;
case 6:
exit(1);
break;
default:
cout<<"Wrong Choice"<<endl;
}
}
return 0;
}输出结果
1.Size of the Queue 2.Insert Element into the Queue 3.Delete Element from the Queue 4.Front Element of the Queue 5.Last Element of the Queue 6.Exit Enter your Choice: 1 Size of the Queue: 0 1.Size of the Queue 2.Insert Element into the Queue 3.Delete Element from the Queue 4.Front Element of the Queue 5.Last Element of the Queue 6.Exit Enter your Choice: 2 Enter value to be inserted: 1 1.Size of the Queue 2.Insert Element into the Queue 3.Delete Element from the Queue 4.Front Element of the Queue 5.Last Element of the Queue 6.Exit Enter your Choice: 2 Enter value to be inserted: 2 1.Size of the Queue 2.Insert Element into the Queue 3.Delete Element from the Queue 4.Front Element of the Queue 5.Last Element of the Queue 6.Exit Enter your Choice: 3 Element 1 Deleted 1.Size of the Queue 2.Insert Element into the Queue 3.Delete Element from the Queue 4.Front Element of the Queue 5.Last Element of the Queue 6.Exit Enter your Choice: 2 Enter value to be inserted: 4 1.Size of the Queue 2.Insert Element into the Queue 3.Delete Element from the Queue 4.Front Element of the Queue 5.Last Element of the Queue 6.Exit Enter your Choice: 2 Enter value to be inserted: 7 1.Size of the Queue 2.Insert Element into the Queue 3.Delete Element from the Queue 4.Front Element of the Queue 5.Last Element of the Queue 6.Exit Enter your Choice: 2 Enter value to be inserted: 6 1.Size of the Queue 2.Insert Element into the Queue 3.Delete Element from the Queue 4.Front Element of the Queue 5.Last Element of the Queue 6.Exit Enter your Choice: 4 Front Element of the Queue: 2 1.Size of the Queue 2.Insert Element into the Queue 3.Delete Element from the Queue 4.Front Element of the Queue 5.Last Element of the Queue 6.Exit Enter your Choice: 5 Back Element of the Queue: 6 1.Size of the Queue 2.Insert Element into the Queue 3.Delete Element from the Queue 4.Front Element of the Queue 5.Last Element of the Queue 6.Exit Enter your Choice: 6 Exit code: 1