c - 带有3星点的Malloc

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void alloc (int*** matr, int r, int c)
{
int i, j;
*matr=malloc(r*sizeof(***matr));
for (i=0; i<r; i++)
    *matr[i]=malloc(c*sizeof(**matr));

for (i=0; i<r; i++)
    for (j=0; j<c; j++)
        *matr[i][j]=12;
}

函数原型由老师给出。我收到的错误是细分错误。感谢您的回答！

最佳答案

假设matr已初始化，则该语句

*matr=malloc(r*sizeof(***matr)); // ***matr is of "int" type

应该

*matr = malloc(r*sizeof(int *));   // Allocate an array of "r" int *
//matr[0] = malloc(r*sizeof(int *));

在for循环中，该语句

*matr[i]=malloc(c*sizeof(**matr));  // **mtr is of "int *" type

应该

(*matr)[i] = malloc(c*sizeof(int)); // Allocate an array of "c" int
//matr[0][i] = malloc(c*sizeof(int));

然后将*matr[i][j]=12;更改为(*matr)[i][j]=12;或matr[0][i][j]=12;

请参见工作代码示例：https://ideone.com/hboLKV