abcd0x00

#include <iostream>
#include <cstdio>

using namespace std;

void mystrcpy(char *to, char *from);

int main()
{
    char str1[20], str2[20];
    cout << "enter string: ";
    gets(str1);

    mystrcpy(str2, str1);

    cout << "string copiet: " << str2;
    cin.get();
    return 0;
}

void mystrcpy(char *to, char *from)
{
    while((*to++ = *from++))
        ;
}

#include <iostream>

using namespace std;

int main()
{
    double **p = 0;

    p = new double *;

    int size;
    cout << "Input size: ";
    cin >> size;

    *p = new double[size];

    for (int i = 0; i < size; i++)
        *(*p + i) = 0;

    **p = *(*p + size - 1) = 2;

    cout << "size: " << size << endl;
    for (int i = 0; i < size; i++)
        cout << *(*p + i) << " ";
    cout << endl;

    delete [] *p;
    delete p;
    p = 0;

    return 0;
}

#include <stdio.h>

struct a {
    int a, b, c;
};

struct b {
    double a, b, c, d;
};

struct c {
    char s[100];
};

struct d {
    int a, b, c;
    double n[10];
};

union x {
    struct a a;
    struct b b;
    struct c c;
    struct d d;    
};

typedef struct {
    enum { A, B, C, D } type;
    union x value;
} Obj;

int main(void)
{
    Obj objects[100], *pobj;
    int n;
    int i;

    objects[0].type = A;
    objects[0].value.a.a = 1;
    objects[0].value.a.b = 2;
    objects[0].value.a.c = 3;

    objects[1].type = B;
    objects[1].value.b.a = 1.5;
    objects[1].value.b.b = 2.5;
    objects[1].value.b.c = 3.5;
    objects[1].value.b.d = 4.5;

    objects[2].type = C;
    sprintf(objects[2].value.c.s, "abc");

    objects[3].type = A;
    objects[3].value.a.a = 4;
    objects[3].value.a.b = 5;
    objects[3].value.a.c = 6;

    n = 4;
    
    for (i = 0; i < n; i++) {
        pobj = objects + i;
        switch (pobj->type) {
        case A:
            printf("A: %d %d %d\n",
                   pobj->value.a.a,
                   pobj->value.a.b,
                   pobj->value.a.c);
            break;
        case B:
            printf("B: %g %g %g %g\n",
                   pobj->value.b.a,
                   pobj->value.b.b,
                   pobj->value.b.c,
                   pobj->value.b.d);
            break;
        case C:
            printf("C: %s\n", pobj->value.c.s);
            break;
        case D:
            printf("D: %g\n", pobj->value.d.n[0]);
            break;
        }
    }

    return 0;
}