笔试经历

 早上参加了***科技的笔试；

题目大概涉及了：

进程和线程的区别；栈和堆分配方式的区别；进程间通信的方式；全局变量和全局静态变量的区别

int (*x)() int *x() int (*x[])()
assert函数的作用；const与宏的区别；栈和堆分配方式的区别；#include"xxoo.h"与#include<xxoo.h>的区别

typedef union {long i; int k[5]; char c;} DATE; struct data { int cat; DATE cow; double dog;} too;
DATE max;
则语句 printf("%d",sizeof(struct date)+sizeof(max));的执行结果是
unsigned char *p1;
unsigned long *p2;
p1=(unsigned char *)0x801000;
p2=(unsigned long *)0x810000;

请问p1+5= ;
p2+5= ;
求过程

后面的代码填空做错了

 

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

typedef unsigned int u32;

static void u32_swap(void *a, void *b, int size)
{
    u32 t = *(u32 *)a;
    *(u32 *)a = *(u32 *)b;
    *(u32 *)b = t;
}

static void generic_swap(void *a, void *b, int size)
{
    char t;

    do {
        t = *(char *)a;
        *(char *)a++ = *(char *)b; *(char *)b++ = t;
    } while (--size > 0);
}

void sort(void *base, size_t num, size_t size,
     int (*cmp)(const void *, const void *),
     void (*swap)(void *, void *, int size))
{
    /* pre-scale counters for performance */
    int i = (num/2) * size, n = num * size, c, r;

    if (!swap)
        swap = (size == 4 ? u32_swap : generic_swap);

    /* heapify */
    for ( ; i >= 0; i -= size) {
        for (r = i; r * 2 < n; r = c) {
            c = r * 2;
            if (c < n - size && cmp(base + c, base + c + size) < 0)
              c += size;
            if (cmp(base + r, base + c) >= 0)
            break;
            swap(base + r, base + c, size);
        }
    }

    /* sort */
    for (i = n - size; i >= 0; i -= size) {
        swap(base, base + i, size);
        for (r = 0; r * 2 < i; r = c) {
            c = r * 2;
            if (c < i - size && cmp(base + c, base + c + size) < 0)
               c += size;
            if (cmp(base + r, base + c) >= 0)
               break;
            swap(base + r, base + c, size);
        }
    }
}

int cmpint(const void *a, const void *b)
{
    return *(int *)a - *(int *)b;
}

void printarray(int *array, int size)
{
    int i;

    printf ("-----------start print array size=%d\n", size);

    for (i = 0; i < size; i++)
    {
        printf ("%d ", array[i]);
    }
    printf ("\n");
}

int main()
{
    int i;
    int *a;
    int size = 10;

    a = (int *) malloc(size * sizeof(int));
    if(a == NULL)
    {
        printf ("malloc\n");
        return 0;
    }
    memset(a, 0, sizeof(int) * size );

    srand(time(NULL));

    for (i = 0; i < size; i++)
    {
        a[i] = rand() % 6599;
    }

    printf ("before sort\n");
    printarray(a, size);

    sort(a, size, sizeof(int), cmpint, NULL);

    printf ("after sort\n");
    printarray(a, size);

    for (i = 0; i < size-1; i++)
        if (a[i] > a[i+1]) {
            printf ("sort() failed!\n");
            printf ("a[%d]=%d > a[%d]=%d\n", i, a[i], i+1, a[i+1]);
            break;
        }

    free(a);

    return 0;
}