c++ - 由于 vector 中的值作为函数参数，程序在编译时失败

Question

请看下面的代码

#include <iostream>
#include <iomanip>
#include <vector>
#include <string>
#include <sstream>


using namespace std;
bool isEven(int);


 int number;
 vector<int> inputNumbers;
 string line;

int main()
{    
    cout << "Please enter numbers: ";

    getline(std::cin,line);
    istringstream iss(line);

    while(iss>>number)
    {
        inputNumbers.push_back(number);
    }

    size_t vectorSize = inputNumbers.size();

    for(int i=0;i<vectorSize;i++)
    {
        cout << "Result for number " << i << "is: " << isEven(inputNumbers(i));
    }


}

bool isEven(int number)
{
    if(number%2 == 0)
    {
        return true;
    }
    else
    {
        return false;
    }
}

当我运行这个程序时，它给出了以下错误

"/usr/bin/make" -f nbproject/Makefile-Debug.mk QMAKE= SUBPROJECTS= .build-conf
make[1]: Entering directory `/cygdrive/c/Users/yohan/Documents/NetBeansProjects/Excersice 6'
"/usr/bin/make"  -f nbproject/Makefile-Debug.mk dist/Debug/Cygwin-Windows/excersice_6.exe
make[2]: Entering directory `/cygdrive/c/Users/yohan/Documents/NetBeansProjects/Excersice 6'
mkdir -p build/Debug/Cygwin-Windows
rm -f build/Debug/Cygwin-Windows/EvenNumbers.o.d
g++    -c -g -MMD -MP -MF build/Debug/Cygwin-Windows/EvenNumbers.o.d -o build/Debug/Cygwin-Windows/EvenNumbers.o EvenNumbers.cpp
EvenNumbers.cpp: In function `int main()':
EvenNumbers.cpp:32: error: no match for call to `(std::vector<int, std::allocator<int> >) (int&)'
make[2]: *** [build/Debug/Cygwin-Windows/EvenNumbers.o] Error 1
make[1]: *** [.build-conf] Error 2
make: *** [.build-impl] Error 2
nbproject/Makefile-Debug.mk:79: recipe for target `build/Debug/Cygwin-Windows/EvenNumbers.o' failed
make[2]: Leaving directory `/cygdrive/c/Users/yohan/Documents/NetBeansProjects/Excersice 6'
nbproject/Makefile-Debug.mk:62: recipe for target `.build-conf' failed
make[1]: Leaving directory `/cygdrive/c/Users/yohan/Documents/NetBeansProjects/Excersice 6'
nbproject/Makefile-impl.mk:39: recipe for target `.build-impl' failed


BUILD FAILED (exit value 2, total time: 1s)

如果我删除对 isEven() 的函数调用，就不会发生这种情况。为什么会这样？请帮忙!

Answer 1

将 isEven(inputNumbers(i)) 更改为 isEven(inputNumbers[i])。

您打算访问第 ith<​​ 个输入数字，为此您使用了括号运算符。