1. 將幾行txt內帶空格的數字分別輸入到vector容器內：

#include<iostream>
#include<vector>
#include<string>
#include<sstream>
#include<fstream>
using namespace std;


void main() {

	string str;
	vector<float>s;
	ifstream fin("123.txt");
	while(getline(fin,str))
	{
		float i;
		stringstream ss(str);
		//ss<<str;
		while (ss>>i)
		{
			s.push_back(i);
			cout << i << " ";
		}
		cout << endl;
	}


	getchar();

}
 

2. 將txt檔案內輸入到二維陣列：

12 23 23

43 44 55

23 45 54

#include<iostream>
#include<vector>
#include<string>
#include<sstream>
#include<fstream>
using namespace std;


void main() {
	float a[3][3]{ {0} };
	string str;
	vector<float>s;
	ifstream fin("123.txt");
	int k = 0;
	while(getline(fin,str))
	{
		int x = 0;
		float i;
		stringstream ss(str);
		while (ss>>i)
		{
			a[k][x]=i;
			cout << i << " ";
			x++;
		}
		k++;
		cout << endl;
	}


	for (int i = 0;i < 3;i++) {
		for (int j = 0;j < 3;j++) {
			cout << a[i][j] << " ";
		}
		cout << endl;
	}
	getchar();

}