我想编写c ++代码,它将所有与输入值
长度相同的元素分开#include <iostream>
#include <vector>
using namespace std;
string database[] = {"green", "stupid", "boy", "girl", "forest", "mobile", "morning", "love", "keyboard", "incredible"};
string input;
string count(string input, string database[]){
string lengthFilter[] = {};
int inputLength = input.length();
for (int i = 0; i < database->length(); ++i){
if (database[i].length() == inputLength)
{
lengthFilter[lengthFilter->length()] = database[i];
}
}
return (lengthFilter);
}
int main()
{
cin >> input;
cout << count(input, database);
return 0;
}
但是它给出了错误
main.cpp: In function 'std::__cxx11::string count(std::__cxx11::string, std::__cxx11::string*)':
main.cpp:16:22: error: could not convert 'lengthFilter' from 'std::__cxx11::string [0] {aka std::__cxx11::basic_string<char> [0]}' to 'std::__cxx11::string {aka std::__cxx11::basic_string<char>}'
return (lengthFilter);
^
exit status 1
我无法找到我的错误,请帮助我。
答案 0 :(得分:2)
您介入了内置C ++数组和[]
语法的缺点。这样:
[]
并不总是意味着你认为它意味着什么。其含义因环境而异。在声明中:
string database[] = // ...
这意味着你要声明一个内置数组。但是,在函数参数中:
string count(string input, string database[])
它是一个指针。上述行等同于:
string count(string input, string* database)
另请注意:
string lengthFilter[] = {};
声明一个零大小的内置数组。我不认为这是你想要的,因为内置数组是固定大小的。他们没有调整大小。
所以你应该在这里做的是改为使用std::vector
:
#include <iostream>
#include <vector>
using namespace std;
vector<string> database = {
"green", "stupid", "boy", "girl", "forest", "mobile", "morning", "love",
"keyboard", "incredible"
};
string input;
vector<string> count(string input, const vector<string>& database)
{
vector<string> lengthFilter;
auto inputLength = input.length();
for (const auto& i : database) {
if (i.length() == inputLength) {
lengthFilter.push_back(i);
}
}
return lengthFilter;
}
int main()
{
cin >> input;
for (const auto& i : count(input, database)) {
cout << i << '\n';
}
return 0;
}