c - 将 for 循环中的值存储到数组中？

Question

鉴于此代码:

for (int i = 0; i < 8; i++)
{
    for (int j = 0; j < 4; j++)
    {
        if (col_A[i] == row_B[j])
        {
            printf("%d %d %2.2f\n",
                   row_A[i], col_B[j], val_A[i] * val_B[j]);
            val_D[i] = val_A[i] * val_B[j];
            row_D[i] = row_A[i];
            col_D[j] = col_B[j];
        }
    }
}

输出如下:

1 1 3.00
1 2 3.00
1 1 3.00
2 1 3.00
2 2 4.00
3 1 4.00
3 2 4.00
3 1 6.00

row_D = [ 1 1 2 2 3 3 0 0 ]
col_D = [ 1 1 2 2 0 0 0 0 ]
val_D = [ 3.00 3.00 3.00 4.00 4.00 6.00 0.00 0.00 ]

将值正确存储到 val_D、row_D 和 col_D 中的正确方法是什么？ Row_D 应包含三元组第一列的值，Col_D 应包含第二列，Val_D 应包含第三列。

谢谢。

Answer 1

引入一个计数器变量，并仅在有更新时递增它。

counter = 0
for (int i = 0; i < 8; i++)
{
    for (int j = 0; j < 4; j++)
    {
        if (col_A[i] == row_B[j])
        {
            printf("%d %d %2.2f\n",
                   row_A[i], col_B[j], val_A[i] * val_B[j]);
            val_D[counter] = val_A[i] * val_B[j];
            row_D[counter] = row_A[i];
            col_D[counter] = col_B[j];
            counter = counter + 1;
        }
    }
}