c++ - 将文件数据复制到 int 数组中

Question

我想问我有一个文件，其中的数字按行和列写入:

23 54 433 65 23 
44 3  32  422 43

我想将其复制到二维 int 数组中，但我不知道该怎么做。我想应用一个字符串标记函数，但如何应用它我不知道该怎么做，请指导我一点

谢谢

Answer 1

这个问题有两个答案。其中之一非常简单(假设您知道相关输入文件的列数和行数)。

for (int a=0; a<NUMROW; a++)
    for (int b=0; b<NUMCOL; b++)
        cin>>TWODARRAY[a][b];

所以这很简单。对于可变长度的数据输入，我想出的又长又笨拙的答案更令人兴奋。不过，我已经测试过了，它确实有效。希望每个人都能熟悉指向指针和字符串流的指针。

string in;
int** twoDArray=NULL;
int numRow=0;
int numCol=0;
string** inputHold=NULL;
int inputSize=10;
//Since we're using pointers instead of vectors, 
    //we have to keep track of the end of the array.
inputHold=new string*[inputSize]; 
while (getline(cin,in)){
    //The string in now contains a line of input.
    if (numRow==0)
    //Assuming that the number of inputs per column is the same in each row,
            //we can save on computation by only checking the number of columns once.
    //Performance may be improved here- it might be more efficient to use str.find
        for (string::iterator iter=in.begin(); iter!=in.end(); iter++){
            if (*iter==' ')
                numCol++;
        }
    //Store the string
    inputHold[numRow]=new string(in);

    numRow++;
    if (numRow==inputSize) {
        //If we're at the end of the array, we create a bigger one and repopulate the data.
        string** tmpInput=inputHold;
        int oldsize=inputSize;
        inputSize=inputSize*2;
        inputHold=new string*[inputSize];
        for (int i=0; i<oldsize; i++){
            inputHold[i]=tmpInput[i];
        }
    }
}
//The method that I used to determine the number of columns is mildly flawed-
    //it doesn't account for the end of line.  So, we increment the counter.
numCol=numCol+1;
twoDArray=new int*[numRow];
for (int a=0; a<numRow; a++)
    twoDArray[a]=new int[numCol];
for (int a=0; a<numRow; a++){
    istringstream parser(*(inputHold[a]));
    for (int b=0; b<numCol; b++){
        parser>>twoDArray[a][b];
    }
}

for (int a=0; a<numRow; a++)
    for (int b=0; b<numCol; b++)
        cout<<twoDArray[a][b]<<endl; 

有人有更简单的东西吗？