[英]Error when printing a 2d vector from an object
美好的一天! 我正在制作一個矩陣類,應該打印出矩陣的函數會破壞程序。 我很確定邏輯是正確的,所以我可能在某個地方犯了一個愚蠢的錯誤。 事實是,我似乎找不到。
這是完整的搜索代碼:
#include <iostream>
#include <vector>
using namespace std;
class Matrix{
private:
double determinant;
vector<vector <int> > body;
int ROWS;
int COLUMNS;
public:
int get_rows(){return ROWS;}
int get_columns(){return COLUMNS;}
vector<vector <int> > get_body(){return body;}
//default constructor
Matrix();
//set up constructor
Matrix(int rows, int columns);
};
//creates the matrix and let's the user fill it's value
Matrix :: Matrix(int ROWS, int COLUMNS){
vector< vector<int> > body;
this->ROWS = ROWS;
this->COLUMNS = COLUMNS;
for(int i = 0; i < ROWS; i++){
cout<<"Row " << i << " begins" <<endl;
vector<int> tmp;
for(int z = 0; z < COLUMNS; z++){
cout<<"Column "<< z<< " begins."<<endl;
int temp;
cin >> temp;
tmp.push_back(temp);
}
body.push_back(tmp);
}
}
//default constructor
Matrix:: Matrix(){
vector< vector<int> > body;
}
void print(Matrix a){
for(int i = 0; i < a.get_rows(); i++){
for(int z = 0; z < a.get_columns(); z++){
cout<<a.get_body()[i][z];
}
cout<< endl;
}
}
int main()
{
Matrix a(2, 2);
print(a);
return 0;
}
和主體的破損功能:
void print(Matrix a){
for(int i = 0; i < a.get_rows(); i++){
for(int z = 0; z < a.get_columns(); z++){
cout<<a.get_body()[i][z];
}
cout<< endl;
}
}
您的問題是,在構造函數中,您需要使用名為body
的局部變量而不是類成員。
Matrix :: Matrix(int ROWS, int COLUMNS){
// vector< vector<int> > body;
// ^^^^^^^^^^^^^^^^^^^^^^^^^^ this should not be here!
this->ROWS = ROWS;
this->COLUMNS = COLUMNS;
for(int i = 0; i < ROWS; i++){
cout<<"Row " << i << " begins" <<endl;
vector<int> tmp;
for(int z = 0; z < COLUMNS; z++){
cout<<"Column "<< z<< " begins."<<endl;
int temp;
cin >> temp;
tmp.push_back(temp);
}
body.push_back(tmp);
}
}
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.