…·─━☆ 무한코딩세계

#include <stdio.h>

typedef struct {
  char a;
  char b;
  int c;
} NODE_t;

void printBinary(char i)
{
 int j;
 for (j = 7; j >= 0; j--)
 {
  printf("%d", (i >> j) & 1);
 }
 printf(" ");
}

void run5()
{
 char *ptr;   
 int idx;

    NODE_t node;
 node.a = 0x65;
 node.b = 0xf0;
 node.c = 0x01020304;

 ptr = (char *)&node;

 for (idx = 0; idx < sizeof(NODE_t); idx++)
 {
  printBinary(*ptr++);
 }
}

#include <stdio.h>

void change(int * n) //general way

{
 char *p = (char *)n;
 char t;
 t = p[0], p[0] = p[3], p[3] = t;
 t = p[1], p[1] = p[2], p[2] = t;
}

void change(int *n)
{
 printf("%d\n", (*n << 24));                    

 //   0100 0000 0000 0000 0000 0000 0000 0000 (0x04000000)

 printf("%d\n", ((*n << 8) & 0xff0000));      

//    0000 0010 0000 0011 0000 0100 0000 0000 (0x02030400)

// & 0000 0000 1111 1111 0000 0000 0000 0000 (0x00ff0000) 

//    0000 0000  0000 0011 0000 0000 0000 0000 (0x00030000)

 printf("%d\n", ((*n >> 8) & 0xff00) );        

//    0000 0000 0000 0001 0000 0010 0000 0011    (0x00010203)

// & 0000 0000 0000 0000 1111 1111 0000 0000    (0x0000ff00)

//    0000 0000 0000 0000 0000 0010 0000 0000    (0x00000200)

 printf("%d\n", (*n >> 24));                    

//    0000 0000 0000 0000 0000 0000 0000 0001    (0x00000001)

 *n = (*n << 24) | ((*n << 8) & 0x00ff0000) | ((*n >> 8) & 0x0000ff00) | (*n >> 24);
}

main()
{
 int xData = 0x01020304;
 char *ptr = (char*)&xData;

 printf("x = %d%d%d%d\n", ptr[0], ptr[1], ptr[2], ptr[3]);
 change1(&xData);
 printf("x = %d%d%d%d\n", ptr[0], ptr[1], ptr[2], ptr[3]);
}

#include <iostream>
#include <stdlib.h>

using namespace std;

class BINARY{
    private:
       
    public:
       int find(int*,int,int,int);
};   

int BINARY::find(int* arrs, int start,int end, int data)
{
    int middle;
    middle = (start + end) / 2;
    if(start < end)
    {
        if(arrs[middle] < data)
                start = middle + 1;
        else if(arrs[middle] > data)
                end = middle - 1;
        else if(arrs[middle] == data)
                return middle;
        return find(arrs, start,end, data);
    }
    return -1;   
}   

int main()
{
    int arr[10] = {111,124,345,366,388,566,777,889,1000,1002};
    int dex;
    BINARY b;
    dex = b.find(arr,0,10,566);
    if(dex == -1) cout<<"없음"<<endl;
    else cout<<dex<<endl;
   
    system("pause");
    return 0;
}