Pass a multidimensional array to a function using a pointer form and reference and modify a multidimensional array using a pointer inside the function

Define a double two-dimensional array A and another equal-sized double-empty two-dimensional array B, and write a function that copies the data in A to B. and test the program.

1#include <stdio.h>2 voidCopy_ptr (Const Double(*s) [ A],Double(*tar) [ A],intRowintcol);3 intMainvoid){4     Const Doublerain[5][ A]={5{4.3,4.3,4.3,3.0,2.0,1.2,0.2,0.2,0.4,2.4,3.5,6.6},6{8.5,8.2,1.2,1.6,2.4,0.0,5.2,0.9,0.3,0.9,1.4,7.3},7{9.1,8.5,6.7,4.3,2.1,0.8,0.2,0.2,1.1,2.3,6.1,8.4},8{7.2,9.9,8.4,3.3,1.2,0.8,0.4,0.0,0.6,1.7,4.3,6.2},9{7.6,5.6,3.8,2.8,3.8,0.2,0.0,0.0,0.0,1.3,2.6,5.2}Ten},t1[5][ A]; OneCopy_ptr (RAIN,T1,5, A); A     //printf ("%.2f", T1[3][8]); -     return 0; - } the voidCopy_ptr (Const Double(*s) [ A],Double(*tar) [ A],intRowintCol) { -     inti,j; -      for(i=0; i<row;i++){ -          for(j=0; j<col;j++){ +* (* (tar+i) +j) =* (* (s+i) +j); -         } +     } A}

The two-dimensional array parameters in function prototypes and function definitions are

Double (*s) [+]

This means that the function accepts a pointer parameter that points to an array with 12 double values. That is, a sub-array.

Because the subarray itself is a pointer to each single double value, here the meaning of double (*s) [] is "s is a pointer, it points to (a step of 1 double, the range is a pointer of 0~11)", and the step of S is the total range of the pointer it points to.

In sum, the multidimensional array is actually behind the value, which implies a pointer tree. Or a pointer chain might be more accurate. Because the pin actually does not exist when an address is not pointed, the path from top to bottom is always unique at a point in time, so it is chained.

Pass a multidimensional array to a function using a pointer form and reference and modify a multidimensional array using a pointer inside the function