# 1.二维数组

#include <stdio.h>
#include <stdlib.h>
void main()
{
int a[3][4] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 };
for (int i = 0; i < 3; i++)
{
for (int j = 0; j < 4; j++)
{
printf("%d,%d,%d,%x,%x   ", a[i][j], *(a[i] + j), *(&a[i][j]), &a[i][j],a[i]+j);
}
printf("\n");
}
//a[x],代表第x行第一个元素首地址 ,某一行这个数组的手地址
printf("\n\na[0]=%x,a[1]=%x,a[2]=%x", a[0], a[1], a[2]);
system("pause");
}  

# 2.二分查找法

while/for 两种方式实现

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

void ShowArray(int a[], int n)
{
for (int i = 0; i < n; i++)
{
printf("%d,", a[i]);
}
printf("\n");
}

void PaiXu(int a[], int n)
{
for (int i = 0; i < n - 1; i++)
{
for (int j = 0; j < n - 1 - i; j++)
{
if (a[j]>a[j+1])
{
int temp = a[j];
a[j] = a[j + 1];
a[j + 1] = temp;
}
}
}
}
//num为所要查找的数据,返回数组下标
int SearchFor(int a[], int n, int num)
{
for (int tou = 0, wei = n - 1, zhong = (tou + wei) / 2; tou <= wei; zhong=(tou+wei)/2)
{
printf("\n开始查找%d,%d,%d", tou, wei, zhong);
if (a[zhong] == num)
{
return zhong;
}
else   if (a[zhong]>num)
{
wei = zhong - 1;
}
else
{
tou = zhong + 1;
}
}
}

int SearchWhile(int a[], int n, int num)
{
int tou = 0;
int wei = n - 1;
int zhong = (tou + wei) / 2;
while (tou <= wei)
{
printf("\n开始查找%d,%d,%d", tou, wei, zhong);
if (a[zhong] == num)
{
return zhong;
}
else   if (a[zhong]>num)
{
wei = zhong - 1;
zhong = (tou + wei) / 2;
}
else
{
tou = zhong + 1;
zhong = (tou + wei) / 2;
}
}
}

void main()
{
int a[50] = { 0 };
time_t ts;
srand((unsigned int)time(&ts));//随机数种子
for (int i = 0; i < 50; i++)
{
a[i] = rand() % 100;
//printf("%d,", a[i]);
}

PaiXu(a, 50);
ShowArray(a, 50);

int num;
scanf("%d", &num);	//扫描数据接收输入
//int ret = SearchFor(a, 50, num);
int ret = SearchWhile(a, 50, num);
if (ret == -1)
{
printf("not find\n");
}
else
{
printf("find [%d]\n", a[ret]);
}
system("pause");
}

# 3.指针、函数指针

void(*p1)() = (void(*)())0x2a1118;//函数地址0x2a1118
p1();

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

{
return a + b;
}

void main()
{
int n = 100;
int *p = &n;
*p = 50;
printf("%d\n", n);

int(*pf)(int, int);//函数指针
printf("%d\n", pf(3, 5));

system("pause");
}

#include <stdio.h>
#include <stdlib.h>
char a = 'A';
char b = 'B';
char c = 'C';
void change(char **pp)
{
*pp = &b;
//**pp = 'D';
}
void main()
{
char *p = &a;
printf("我的等级为：[%c]\n", *p);
change(&p);
printf("我的等级为：[%c]\n", *p);
system("pause");
} 

# 4.模块注射

DllInject.exe 工具

_declspec(dllexport) void go()//导出为dll模块；

#include <stdio.h>
#include <stdlib.h>
#include <Windows.h>

char a = 'A';
char b = 'B';
char c = 'C';

void main()
{
char *p = NULL;
p = &a;
printf("p=%x,&a=%x,&b=%x,&c=%x\n", p, &a, &b, &c);
while (1)
{
printf("我的等级为：[%c]\n", *p);
Sleep(10000);//10s
}
}

_declspec(dllexport) void go()//导出为dll模块；
{
char **pp = (char **)0x288000;//得到p的地址
*pp = (char *)0x288002;//等级C的地址
}

+ 订阅