c - 这些陈述是什么意思？

Question

#include<stdio.h>
void main() {
 int s[4][2]={
               {1,2},
               {3,4},
               {5,6},
               {7,8}
             };
int (*p)[2]; // what does this statement mean? (A)
int i,j,*pint;

for(i=0;i<=3;i++) {
 p=&s[i];
 pint=(int*)p;  // what does this statement mean? (B)
 printf("\n");
  for(j=0;j<=1;j++) {
    printf("%d",*(pint+j));
  }
}

我无法理解声明“A”和“B”。如何以及已完成哪些工作？请解释清楚。

Answer 1

语句A是声明

int (*p)[2];      ^      p isint (*p)[2];     ^       p is a pointerint (*p)[2];        ^    p is a pointer to an arrayint (*p)[2];         ^   p is a pointer to an array of 2int (*p)[2];^^^          p is a pointer to an array of 2 int

语句 B 是一个嵌入了强制类型转换的赋值表达式

pint=(int*)p;           ^  take the value in p (of type "pointer to array of 2 ints")pint=(int*)p;     ^^^^^^   take the value in p, convert it to 'pointer to int'              even if it doesn't make sense to do sopint=(int*)p;^^^^^         take the value in p, convert it to 'pointer to int'              and put the resulting value (whatever that may be) in pint

类型转换不好。尽可能避免转换。
^{(*) 除非在非常特殊的情况下，例如 <ctype.h>或可变函数或 ...}