问如何使用宏参数声明变量

EN

// Put your macro definitions here.  That should be all
// you need to do to complete this exercise.
#define DECL_LIST(type, name) \
    int name ## _cap = 5;     \
    int name ## _len = 0;     \
    type *name = (type *) malloc(name ## _cap * sizeof(type)); 

#define CHECK_CAP(type, name)                                         \
if ( name ## _len >= name ## _cap ) {                                 \
name ## _cap *= 2;                                                    \
name = (type *) realloc(name, name ## _cap * sizeof(type)); \
}  

#define SIZE(name)    \
sizeof(name)/sizeof(name[0]) 


#define FOR(var, limit) { \
  int var = 0;  \
for( int i = 0; i < limit; i++) {          \
       var++;           \
}    \
}

#define SWAP(type, a, b)   \
type temp = a; \
   a = b; \
   b = temp; 


int main()
{
  // Make a resizable list.
  DECL_LIST( double, list );

  double val;
  while ( scanf( "%lf", &val ) == 1 ) {
    // Grow the list when needed.
    CHECK_CAP( double, list );

    // Add this item to the list
    list[ SIZE( list ) ] = val;
    SIZE( list ) += 1;
  }

  // Bubble-sort the list.
  FOR( i, SIZE( list ) )
    FOR( j, SIZE( list ) - i - 1 )
      if ( list[ j ] > list[ j + 1 ] )
        SWAP( double, list[ j ], list[ j + 1 ] );

  // Print out the resulting, sorted list, one value per line.
  FOR( i, SIZE( list ) )
    printf( "%.2f\n", list[ i ] );

  return EXIT_SUCCESS;
}

#include <stdio.h>
#include <stdlib.h>
int main()
{
// Make a resizable list.
int list_cap = 5;
int list_len = 0;
double *list = (double *) malloc( list_cap * sizeof( double ) );
double val;
while ( scanf( "%lf", &val ) == 1 ) {
// Grow the list when needed.
if ( list_len >= list_cap ) {
list_cap *= 2;
list = (double *) realloc( list, list_cap * sizeof( double ) );
}
// Add this item to the list
list[ list_len ] =val;
list_len++;
}
// Bubble-sort the list.
for ( int i = 0; i < list_len; i++ )
for ( int j = 0; j < list_len - i - 1; j++ )
if ( list[ j ] > list[ j + 1 ] ) {
double tmp = list[ j ];
list[ j ] = list[ j + 1 ];
list[ j + 1 ] = tmp;
}
// Print out the resulting, sorted list, one value per line.
for ( int i = 0; i < list_len; i++ )
printf( "%.2f\n", list[ i ] );
return EXIT_SUCCESS;
}

error: lvalue required as left operand of assignment
     SIZE( list ) += 1;
                  ^
sortList.c:50:8: warning: unused variable ‘i’ [-Wunused-variable]
   FOR( i, SIZE( list ) )
        ^
sortList.c:22:7: note: in definition of macro ‘FOR’
   int var = 0;  \
       ^
sortList.c:52:18: error: ‘j’ undeclared (first use in this function)
       if ( list[ j ] > list[ j + 1 ] )
                  ^
sortList.c:52:18: note: each undeclared identifier is reported only once for each function it appears in
sortList.c:53:15: error: expected expression before ‘double’
         SWAP( double, list[ j ], list[ j + 1 ] );
               ^
sortList.c:29:1: note: in definition of macro ‘SWAP’
 type temp = a; \
 ^
sortList.c:31:8: error: ‘temp’ undeclared (first use in this function)
    b = temp; 
        ^
sortList.c:53:9: note: in expansion of macro ‘SWAP’
         SWAP( double, list[ j ], list[ j + 1 ] );
         ^
sortList.c:56:8: warning: unused variable ‘i’ [-Wunused-variable]
   FOR( i, SIZE( list ) )
        ^
sortList.c:22:7: note: in definition of macro ‘FOR’
   int var = 0;  \
       ^
sortList.c:57:29: error: ‘i’ undeclared (first use in this function)
     printf( "%.2f\n", list[ i ] );