如何确定C++中向量的值个数? 我试图用C++构建一个小任务,我需要让用户预先确定他们想要在GrassPayCuffsSvector向量中放置多少个GoffsPayPayChest.
到目前为止,这就是我所拥有的:如何确定C++中向量的值个数? 我试图用C++构建一个小任务,我需要让用户预先确定他们想要在GrassPayCuffsSvector向量中放置多少个GoffsPayPayChest.,c++,c++11,vector,cin,C++,C++11,Vector,Cin,到目前为止,这就是我所拥有的: vector<double> gross_paychecks_vector (5); double gross_paychecks; // Add 5 doubles to vector cout << "Please enter an integer" << endl; cin >> gross_paychecks; for(gross_paychecks = 0; gross_paycheck
vector<double> gross_paychecks_vector (5);
double gross_paychecks;
// Add 5 doubles to vector
cout << "Please enter an integer" << endl;
cin >> gross_paychecks;
for(gross_paychecks = 0; gross_paychecks <= gross_paychecks_vector; ++gross_paychecks ){
cin >> gross_paychecks;
}
现在我有点不知所措,因为我不确定是否要将向量切换到类似向量gross_paychecks{}的东西,因为它在for循环中抛出了一个错误
另外,我不确定如何使用for循环,我应该使用for循环还是其他什么?。我需要接受用户的输入,只要它没有达到他/她指定的总工资支票数。您可能需要:
vector<double> gross_paychecks_vector; // initially the vector is empty
...
cout << "How many paychecks:" << endl;
cin >> gross_paychecks;
for (int i = 0; i < gross_paychecks; i++)
{
double value;
cin >> value;
gross_paychecks_vector.push_back(value); // add new value to vector
}
// display values in vector
for (auto & value : gross_paychecks_vector)
{
cout << value << "\n";
}
另外。如果您想使用现代C++特性,您将使用:
#include <iostream>
#include <algorithm>
#include <iterator>
#include <vector>
int main()
{
std::vector<double> grossPaychecks{};
std::cout << "How many paychecks:\n";
size_t numberOfPaychecks{0};
std::cin >> numberOfPaychecks;
// Read all data
std::copy_n(std::istream_iterator<double>(std::cin),numberOfPaychecks, std::back_inserter(grossPaychecks));
// Print all data
std::copy(grossPaychecks.begin(), grossPaychecks.end(), std::ostream_iterator<double>(std::cout,"\n"));
return 0;
}