demo_3_13

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include <string.h>
#include <stdlib.h>


int main()
{
    unsigned char a = 0x5b, b = 0xf0;
    printf("%x\n", (a&b) >> 4);
    system("pause");
    return 0;
}

int main()
{
    int i = 0, j = 0;
    while (++i)
    {
        if (i % 3 == 0) continue;
        else j += i;
        if (i > 5) break;
    }
    printf("%d\n", j);
    system("pause");
    return 0;
}

int main()
{
    int w[15] = { 55, 19, 13, 8, 5, 5, 1 }, n = 7, x = 15, i, pos = 0;
    while (x < w[pos]) pos++;
    for (i = 0; i>pos; i--) w[i] = w[i-1];
    w[pos] = x;
    n++;
    for (i = 0; i < n; i++) printf("%d, ", w[i]);
    printf("\n");
    system("pause");
    return 0;
}

void fun(int * x)
{
    static int a;
    *x = ++a;
}
int main()
{
    int i, t;
    for (i = 0; i < 10; i++)
    {
        fun(&t);
    }
    printf("%d\n", t);
    system("pause");
    return 0;
}

int main()
{
    int i;
    for (i = 3; i < 10; i++)
    {
        if (i*i / 20>1) break;
        printf("%d ", i);
    }
    printf("\n");
    system("pause");
    return 0;
}

enum color
{
    red,
    blue=-3,
    yellow,
    green
};
int main()
{
    enum color cr = green;
    printf("%d\n", cr);
    system("pause");
    return 0;
}

struct node
{
    int data;
    struct node *next;
};
void fun(struct node * head)
{
    struct node * p = head;
    while (p != NULL)
    {
        printf("%d ", p->data);
        p = p->next;
    }
}
int main()
{
    system("pause");
    return 0;
}

int main()
{
    int n, yw, s = 0, t=1;
    printf("输入一个整型数字:>");
    scanf("%d", &n);
    while (n != 0)
    {
        yw = n % 10;
        s = s + yw;
        t = t*yw;
        n = n / 10;
    }
    printf("s=%d,t=%d\n", s, t);
    system("pause");
    return 0;
}


char *find_str(char *s1, char *s2)
{
    int i, j, ls2;
    ls2 = strlen(s2);
    for (i = 0; i < strlen(s1) - ls2; i++)
    {
        for (j = 0; j < ls2; j++) if (s1[j + i] != s2[j]) break;
        if (j == ls2) return (s1 + i);
    }
    return NULL;
}
int main()
{
    char *a = "dos6.22 windows98 office2000", *b = "windows", *c;
    c = find_str(a, b);
    if (c != NULL) printf("%s\n", c);
    else printf("未找到字符串%s\n", b);
    system("pause");
    return 0;
}

#define N 100
int main()
{
    int i, j, n, a[N] = { 0 };
    n = 1; a[0] = 1;
    for (i = 1; i <= N; i++)
    {
        for (j = n - 1; j >= 0; j--) a[j] *= 2;
        for (j = 0; j < n; j++)
        {
            a[j + 1] += a[j] / 10;
            a[j] %= 10;
        }
        if (a[n]) n++;
    }
    for (i = n - 1; i >= 0; i--)
    {
        printf("%d ", a[i]);
    }
    printf("\n");
    system("pause");
    return 0;
}

int main()
{
    int i, k, a[52], temp;
    for (i = 0; i < 52; i++) a[i] = i;
    randomize();
    for (i = 51; i>0; i--)
    {
        k = random(i);
        temp = a[i];
        a[i] = a[k];
        a[k] = temp;
    } 
    printf("洗好后扑克牌的顺序为:\n");
    for (i = 0; i < 52; i++)
    {
        printf("%5d%c", a[i], ((i + 1) % 4) ? ' ' : '\n');
    }
    system("pause");
    return 0;
}

int main()
{
    int x = 5, y = 2;
    int s;
    (y = 2 + x), x++, 2 * y;
    printf("%d\n", s);
    system("pause");
    return 0;
}

int main()
{
    char a = 'a';
    a--;
    printf("%d,%c\n", a + ' 2' - '0', a + ' 3' = '0');
    system("pause");
    return 0;
}

int main()
{
    int i, j, x = 0;
    for (i = 0; i < 2; i++)
    {
        x++;
        for (i = 0; i < 2; i++)
        {
            if (j % 2) continue;
            x++;
        }
        x++;
    }
    printf("x=%d\n", x);
    system("pause");
    return 0;
}

int main()
{
    int i, j, x = 0;
    for (i = 0; i < 2; i++)
    {
        x++;
        for (j = 0; j <= 3; j++)
        {
            if (j % 2) continue;
            x++;
        }
        x++;
    }
    printf("x=%d\n", x);
    system("pause");
    return 0;
}

int main()
{
    int x = 1, y = 0, a = 0, b = 0;
    switch (x)
    {
    case 1:
        switch (y)
        {
        case 0:a++; break;
        case 1:b++; break;
        }
    case 2:a++; b++; break;
    case 3:a++; b++; break;
    }
    printf("a=%d,b=%d\n", a, b);
    system("pause");
    return 0;
}

int main()
{
    int y = 10;
    while (y--)
    {
        ;
    }
    printf("y=%d\n", y);
    system("pause");
    return 0;
}

int main()
{
    int a[] = { 1, 2, 3, 4, 5, 6 }, *p;
    p = a;
    *(p + 3) += 2;
    printf("%d,%d\n", *p, *(p + 3));
    system("pause");
    return 0;
}

int main()
{
    char *sp = "\t\v\\\0will\n";
    printf("%d\n", strlen(sp));
    system("pause");
    return 0;
}

#define M 3
#define N M+1
#define NN N*N/2
int main()
{
    printf("%d\n", NN);
    printf("%d\n", 5 * NN);
    system("pause");
    return 0;
}