实现矢量的C ++程序
向量是一个动态数组，如果插入或删除元素，它可以调整自身大小。向量元素包含在连续的存储中，并且容器自动处理该存储。
实现矢量的程序如下所示-
示例
#include <iostream>
#include <vector>
#include <string>
#include <cstdlib>
using namespace std;
int main() {
int ch, val;
vector<int> vec;
cout<<"1)Insert Element into the Vector"<<endl;
cout<<"2)Delete Last Element of the Vector"<<endl;
cout<<"3)Print size of the Vector"<<endl;
cout<<"4)Display Vector elements"<<endl;
cout<<"5)Clear the Vector"<<endl;
cout<<"6)Exit"<<endl;
do {
cout<<"Enter your Choice: "<<endl;
cin>>ch;
switch(ch) {
case 1:
cout<<"Enter value to be inserted: "<<endl;
cin>>val;
vec.push_back(val);
break;
case 2:
cout<<"Last Element is deleted."<<endl;
vec.pop_back();
break;
case 3:
cout<<"Size of Vector: ";
cout<<vec.size()<<endl;
break;
case 4:
cout<<"Displaying Vector Elements: ";
for (int i = 0; i < vec.size(); i++)
cout<<vec[i]<<" ";
cout<<endl;
break;
case 5:
vec.clear();
cout<<"Vector Cleared"<<endl;
break;
case 6:
cout<<"Exit"<<endl;
break;
default:
cout<<"Error....Wrong Choice Entered"<<endl;
}
} while (ch!=6);
return 0;
}输出结果
上面程序的输出如下
1)Insert Element into the Vector 2)Delete Last Element of the Vector 3)Print size of the Vector 4)Display Vector elements 5)Clear the Vector 6)Exit Enter your Choice: 1 Enter value to be inserted: 5 Enter your Choice: 1 Enter value to be inserted: 2 Enter your Choice: 1 Enter value to be inserted: 8 Enter your Choice: 1 Enter value to be inserted: 6 Enter your Choice: 3 Size of Vector: 4 Enter your Choice: 4 Displaying Vector Elements: 5 2 8 6 Enter your Choice: 2 Last Element is deleted. Enter your Choice: 3 Size of Vector: 3 Enter your Choice: 4 Displaying Vector Elements: 5 2 8 Enter your Choice: 5 Vector Cleared Enter your Choice: 3 Size of Vector: 0 Enter your Choice: 4 Displaying Vector Elements: Enter your Choice: 9 Error....Wrong Choice Entered Enter your Choice: 6 Exit
在上述程序中，首先定义矢量，然后向用户提供菜单以选择矢量操作。这在下面给出-
vector<int> vec; cout<<"1)Insert Element into the Vector"<<endl; cout<<"2)Delete Last Element of the Vector"<<endl; cout<<"3)Print size of the Vector"<<endl; cout<<"4)Display Vector elements"<<endl; cout<<"5)Clear the Vector"<<endl; cout<<"6)Exit"<<endl;
使用dowhile循环输入用户选择，并使用switch语句根据选择执行操作。不同的操作是将元素插入向量，从向量中删除元素，向量的打印大小，向量的显示元素，清除向量以及退出。下面的代码片段如下-
do {
cout<<"Enter your Choice: "<<endl;
cin>>ch;
switch(ch) {
case 1:
cout<<"Enter value to be inserted: "<<endl;
cin>>val;
vec.push_back(val);
break;
case 2:
cout<<"Last Element is deleted."<<endl;
vec.pop_back();
break;
case 3:
cout<<"Size of Vector: ";
cout<<vec.size()<<endl;
break;
case 4:
cout<<"Displaying Vector Elements: ";
for (int i = 0; i < vec.size(); i++)
cout<<vec[i]<<" ";
cout<<endl;
break;
case 5:
vec.clear();
cout<<"Vector Cleared"<<endl;
break;
case 6:
cout<<"Exit"<<endl;
break;
default:
cout<<"Error....Wrong Choice Entered"<<endl;
}
} while (ch!=6);