据我所知，NAN可以分配给double类型变量，但不一定分配给int/size_t
是否还有方法使用NAN填充int/size_t类型的向量/矩阵？

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

typedef struct {
  size_t nrows, ncols;
  size_t *array;
} Matrix ;

size_t ncol = 5;
size_t nrow = 1;

void print_matrix(Matrix * matrix);

int main()
{
  Matrix *mat1 = (Matrix *) malloc(sizeof(Matrix));
  mat1->nrows = nrow;
  mat1->ncols = ncol;
  mat1->array = (size_t *) malloc(mat1->nrows * mat1->ncols * sizeof(*mat1->array));
  if (mat1 == NULL)
  {
    printf("Could not allocate memory\n");
    exit(EXIT_FAILURE);
  }
  else
  {
    mat1->nrows = nrow;
    mat1->ncols = ncol;
    mat1->array = (size_t *) malloc(mat1->nrows * mat1->ncols * sizeof(*mat1->array));
    for (size_t row =0; row<mat1->nrows; row++)
    {
      for (size_t col =0; col<mat1->ncols; col++)
      {
        mat1->array[row * ncol + col] = NAN;
      }
    }
    print_matrix(mat1);
    free(mat1);
  }
}

void print_matrix(Matrix * matrix)
{
  for (size_t row =0; row<matrix->nrows; row++)
  {
    for (size_t col =0; col<matrix->ncols; col++)
    {
      printf("%zu ", matrix->array[row * ncol + col]);
    }
    printf("\n");
  }
}