demo_3_19

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include <stdlib.h>
int d = 1;
void fun(int p)
{
    int d = 5;
    d += p++;
    printf("%d ", d);
}
int main()
{
    int a = 3;
    fun(a);
    d += a++;
    printf("%d\n", d);
    system("pause");
    return 0;
}

int fun(int a)
{
    int b = 0;
    static int c = 3;
    a = (c++, b++);
    return (a);
}
int main()
{
    int a = 2, i, k;
    for (i = 0; i < 2; i++) k = fun(a++);
    printf("%d\n", k);
    system("pause");
    return 0;
}

int main()
{
    char c[2][5] = { "6934", "8254" }, *p[2];
    int i, j, s = 0;
    for (i = 0; i < 2; i++) p[i] = c[i];
    for (i = 0; i < 2; i++)
    {
        for (j = 0; p[i][j]>0 && p[i][j] <= '9'; j += 2)
        {
            s = 10 * s + p[i][j] - '0';
        }
    }
    printf("%d\n", s);
    system("pause");
    return 0;
}


void fun(double *p1, double *p2, double *s)
{
    s = (double *)calloc(1, sizeof(double));
    *s = *p1 + *(p2 + 1);
}
int main()
{
    double a[2] = { 1.1, 2.2 }, b[2] = { 10.0, 20.0 }, *s = a;
    fun(a, b, s);
    printf("%5.2f\n", *s);
    system("pause");
    return 0;
}

int main()
{
    int a, b;
    for (a = 1, b = 1; a <= 100; a++)
    {
        if (b >= 20) break;
        if (b % 3 == 1){ b = b + 3; continue; }
        b = b - 5;
    }
    printf("%d\n", a);
    system("pause");
    return 0;
}


void fun(int x, int y, int *c, int *d)
{
    *c = x + y;
    *d = x - y;
}
int main()
{
    int a = 4, b = 3, c = 0, d = 0;
    fun(a, b, &c, &d);
    printf("%d %d\n", c, d);
    system("pause");
    return 0;
}

int main()
{
    int a[] = { 2, 4, 6, 8, 10 }, x, *p, y = 1;
    p = &a[1];
    for (x = 0; x < 3; x++)
    {
        y += *(p + x);
    }
    printf("%d\n", y);
    system("pause");
    return 0;
}


char fun(char *c)
{
    if (*c <= 'Z'&&*c >= 'A')
    {
        *c -= 'A' - 'a';
    }
    return *c;
}
int main()
{
    char s[81], *p = s;
    gets(s);
    while (*p)
    {
        *p = fun(p);
        putchar(*p);
        p++;
    }
    printf("\n");
    system("pause");
    return 0;
}

int fun(char *s)
{
    char *p = s;
    while (*p != 0) p++;
    return (p - s);
}
int main()
{
    printf("%d\n", fun("goodbey!"));
    system("pause");
    return 0;
}

int main()
{
    printf("%x\n", (0x19 << 1) & 0x17);
    system("pause");
    return 0;
}

int main()
{
    int k, s;
    for (k = 0, s = 0; k < 10; k++)
    {
        if (s>k) break;
        else s += k;
    }
    printf("k=%d s=%d\n", k, s);
    system("pause");
    return 0;
}


#define MIN(x,y) (x)<(y)?(x):(y)
int main()
{
    printf("%d\n", 10 * MIN(10, 15));
    system("pause");
    return 0;
}

int f(int m)
{
    static int k = 0;
    int s = 0;
    for (; k <= m; k++)
    {
        s++;
    }
    return s;
}
void main()
{
    int s1, s2;
    s1 = f(5);
    s2 = f(3);
    printf("%d %d\n", s1, s2);
    system("pause");
    return 0;
}


int a = 5;
fun(int b)
{
    static int a = 10;
    a += b++;
    printf("%d ", a);
}
int main()
{
    int c = 20;
    fun(c);
    a += c++;
    printf("%d\n", a);
    system("pause");
    return 0;
}

typedef union student
{
    char name[10];
    long sno;
    char sex;
    float score[4];
}STU;
int main()
{
    STU a[5];
    printf("%d\n", sizeof(a));
    system("pause");
    return 0;
}

int main()
{
    char c;
    while ((c = getchar()) != '?') putchar(--c);
    system("pause");
    return 0;
}

int main()
{
    int p, a = 5;
    if (p = a != 0) printf("%d\n", p);
    else printf("%d\n", p + 2);
    system("pause");
    return 0;
}

#define SUM(x) x+x
int main()
{
    int a = 10, k = 3, m = 2;
    a /= SUM(k*m) / SUM(m);
    printf("%d\n", a);
    system("pause");
    return 0;
}

int main()
{
    int x = 3;
    do{
        printf("%d ", x -= 2);
    } while (!(--x));
    system("pause");
    return 0;
}

int main()
{
    union
    {
        long k;
        int i[6];
        char c[4];
    }r;
    printf("%d\n", sizeof(r));
    system("pause");
    return 0;
}


int maxop(int m, int n)
{
    if (m > n) return maxop(m - n, n);
    if (m < n) return maxop(m, n - m);
    if (m == n) return m;
}
int main()
{
    printf("%d\n", maxop(85, 51));
    system("pause");
    return 0;
}


#define PI 3.14
#define AREA(x) PI*x*x
void main()
{
    float radius = 1.0, area;
    area = AREA(radius + 1);
    printf("%5.2f\n", area);
    system("pause");
}