C/C++常用开发代码片段

由于内容较少,所以,不想把它放在我的本地博客中了,暂时保存在这里,代码有一部分来源于网络,比较经典的案例,同样收藏起来。

Stack 栈容器

Stack容器适配器中的数据是以LIFO的方式组织的,它是一种先进后出的数据结构,栈允许对元素进行新增,移除,获取栈顶,等操作,但栈不允许对内部元素进行遍历,只能访问栈顶部的元素,只有在移除栈顶部的元素后,才能访问下方的元素.

Stack 压栈/出栈:

#include <iostream>
#include <stack>
using namespace std;

int main(int argc, char* argv[])
{
stack<int> st;

st.push(1); // 入栈
st.push(2);

while (!st.empty() || st.size()!=0)
{
cout << "pop -> " << st.top() << endl;
st.pop(); // 出栈
}
system("pause");
return 0;
}

heap 堆容器

入堆

#include <iostream>
#include <algorithm>
#include <vector>

using namespace std;

void print(int x){ cout << x << " "; }

int main(int argc, char* argv[])
{
vector<int> v;

v.push_back(1);
v.push_back(2);
v.push_back(3);

push_heap(v.begin(), v.end()); // 入堆
for_each(v.begin(), v.end(), print);
system("pause");
return 0;
}
#include <iostream>
#include <algorithm>
#include <vector>

using namespace std;


void print(int x){ cout << x << " "; }

int main(int argc, char* argv[])
{
vector<int> v;

v.push_back(1);
v.push_back(2);
v.push_back(3);

make_heap(v.begin(), v.end()); // 创建堆

push_heap(v.begin(), v.end()); // 入堆

for_each(v.begin(), v.end(), print);

pop_heap(v.begin(), v.end());

for_each(v.begin(), v.end(), print);
system("pause");
return 0;
}

常用的代码片段

数组实现逆序排列: 所谓数组逆序就是讲一个正向数组反向排列,并输出排序后的结果.

#include <stdio.h>

void Swap_Array(int Array[], int Number)
{
int x = 0;
int y = Number - 1;
while (x < y)
{
int tmp;
tmp = Array[x];
Array[x] = Array[y];
Array[y] = tmp;
x++; y--;
}
}

int main(int argc, char* argv[])
{
int Array[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

Swap_Array(Array, 10);

for (int x = 0; x < 10; x++)
{
printf("%d ", Array[x]);
}

system("pause");
return 0;
}

用数组冒泡排序: 冒泡排序是经典的算法,也是学习数组必学知识点,这里总结一份冒泡排序.

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

void bubble(int *arr, int len)
{
int flag = 1;
for (int i = 0; i < len - 1; i++)
{
for (int j = 0; j < len - i - 1; j++)
{
if (arr[j] > arr[j + 1])
{
flag = 0;
int temp = arr[j];
arr[j] = arr[j + 1];
arr[j + 1] = temp;
}
}
if (flag)
return;
flag = 1;
}
}

int main(int argc, char* argv[])
{
int Array[] = {1,2,3,4,5,6,7,8,9,10};

int len = sizeof(Array) / sizeof(int);
bubble(Array, len);

for (int x = 0; x < len; x++)
printf("%d \n", Array[x]);

system("pause");
return 0;
}

打印乘法口诀表:

#include <stdio.h>

int main(int argc, char* argv[])
{
int i, j;
for (i = 1; i <= 9; i++)
{
for (j = 1; j <= i; j++)
{
printf("%d*%d=%d\t", j, i, i*j);
}
printf("\n");
}
system("pause");
return 0;
}

输出随机数与字母: 通过使用<time.h>模块中的rand()函数实现生成随机数.

#include <stdio.h>
#include <time.h>

int main(int argc, char* argv[])
{
srand((unsigned int)time(NULL)); // 设置随机种子
for (int x = 0; x <= 20; x++)
{
int rand_num = rand() % 100 + 1; // 产生 1 - 100 范围内的随机数
printf("1-100以内随机数: %d \n", rand_num);

rand_num = rand() % 25 + 66; // 产生 65 - 90 范围内的随机数
printf("A-Z以内的随机数: %c \n", rand_num);

rand_num = rand() % 25 + 98; // 产生 97 - 122 范围内的随机数
printf("a-z以内的随机数: %c \n", rand_num);
}
system("pause");
return 0;
}

生成随机数字串: 通过循环实现生成随机的字符串,可以用于秘钥计算.

#include <iostream>
#include <time.h>

int GetRandom(int bit){
for (int x = 0; x < bit; x++)
{
int rand_number = 0;
int rand_range = rand() % 4 + 1; // 取 1-3 之间的随机数
switch (rand_range)
{
case 1: // 得到一个整数
rand_number = rand() % 10 + 1;
printf("%d", rand_number);
case 2: // 得到一个小写字母
rand_number = rand() % 25 + 66;
printf("%c", rand_number);
case 3: // 得到一个大写字母
rand_number = rand() % 25 + 98;
printf("%c", rand_number);
default:
continue;
}
}
return 1;
}

int main(int argc, char* argv[])
{
for (int x = 0; x < 3; x++)
{
GetRandom(5);
printf("-");
}
printf("\n");
system("pause");
return 0;
}

随机数去重

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

int main(int argc, char* argv[])
{
srand((unsigned int)time(NULL));

int ran[10];


for (int x = 0; x < 10; x++)
{
ran[x] = rand() % 33 + 1;
// 实现去重
for (int y = 0; y < x; y++)
{
if (ran[x] == ran[y])
{
x--; continue;
}
}
}

for (int x = 0; x < 10; x++)
{
printf("%d ", ran[x]);
}

system("pause");
return 0;
}

时间日期格式化: 将时间与日期格式化成想要的样子然后输出到屏幕上.

#include <iostream>
#include <time.h>

int main(int argc, char* argv[])
{
time_t curtime;
struct tm *info;
char buffer[80];

time(&curtime);
printf("当前时间: %s\n", ctime(&curtime));

info = localtime(&curtime);
info->tm_year = info->tm_year + 1; // 年份向后延期一年
info->tm_mon = info->tm_mon - 2; // 月份向前推2个月

strftime(buffer, 80, "%Y-%m-%d %H:%M:%S", info);
printf("格式化本地时间: %s\n", buffer);

time_t seconds;
seconds = time(NULL);
printf("自 1970-01-01 起的小时数 = %ld\n", seconds / 3600);

system("pause");
return 0;
}

输入日期判断是周几:

#include <iostream>
#include <time.h>

int main(int argc, char* argv[])
{
time_t rawtime;
struct tm *timeinfo;
int year = 2013, month = 12, day=21;
const char *weekday[] = { "周日", "周一", "周二", "周三", "周四", "周五", "周六" };

time(&rawtime);
timeinfo = localtime(&rawtime);
timeinfo->tm_year = year - 1900;
timeinfo->tm_mon = month - 1;
timeinfo->tm_mday = day;
mktime(timeinfo);

printf("%d-%d-%d 是 => %s \n", year,month,day,weekday[timeinfo->tm_wday]);
system("pause");
return 0;
}

计算时间差:

#include <time.h>
#include <iostream>

int main(int argc, char* argv[])
{
clock_t start_t, end_t;
double total_t;
start_t = clock();
for (int i = 0; i< 10000000; i++)
{
}
end_t = clock();
total_t = (double)(end_t - start_t) / CLOCKS_PER_SEC;
printf("CPU 占用的总时间:%f\n", total_t);
system("pause");
return(0);
}

Popen 执行命令

#include <iostream>
#include <stdio.h>

int main(int argc, char* argv[])
{
char buffer[4096];
FILE *fi = _popen("ipconfig", "r");
while (fgets(buffer, 4096, fi) != NULL){
fprintf(stdout, "%s", buffer);
}
system("pause");
return 0;
}

隐藏控制台

#pragma comment( linker, "/subsystem:\"windows\" /entry:\"mainCRTStartup\"" )
#include <stdio.h>

int main()
{
while (1)
printf("a");
return 0;
}

猴子吃桃

#include <stdio.h>
int main(int argc, char *argv[])
{
int day,x1,x2;
day=9;
x2=1;
while(day>0)
{
x1=(x2+1)*2;
x2=x1;
day--;
}
printf ("the total is %d\n",x1);
return 0;
}

穷举灯塔数量

#include <stdio.h>
int main(int argc, char *argv[])
{
int n=1,m,sum,i;
while(1)
{
m=n;
sum=0;
for (i=1; i<8; i++)
{
m=m*2;
sum+=m;
}
sum+=n;
if (sum==765)
{
printf ("the first floor has %d\n",n);
printf ("the eight floor has %d\n",m);
break;
}
n++;
}
return 0;
}

小球下落问题

#include <stdio.h>
int main(int argc, char *argv[])
{
float i,h=100,s=100;
for (i=1; i<=9; i++)
{
h=h/2;
s+=h*2;
}
printf ("the total length is %f\n",s);
printf ("the lenght of tenth time is %f\n",h/2);
return 0;
}

彩球问题

#include <stdio.h>
int main(int argc, char *argv[])
{
int i,j,count;
puts("the result is:\n"); //向屏幕上输出提示信息
printf ("time red ball white ball black ball\n");
count = 1;
for(i=0;i<=3;i++)
for(j=0;j<=3;j++)
if((8-i-j)<=6)
printf ("%3d%7d%12d%12d\n",count++,i,j,8-i-j);
return 0;
}

打印杨辉三角

#include <stdio.h>
int main(int argc, char *argv[])
{
int i,j,a[11][11];
for (i=1; i<11; i++)
{
a[i][i]=1;
a[i][1]=1;
}
for (i=3; i<11; i++)
{
for (j=2; j<=i-1; j++)
{
a[i][j]=a[i-1][j-1]+a[i-1][j];
}
}
for (i=1; i<11; i++)
{
for (j=1; j<=i; j++)
printf ("%4d\t",a[i][j]);
printf ("\n");
}
return 0;
}

打印乘法口决表

#include <stdio.h>
int main(int argc, char *argv[])
{
int i,j;
for (i=1; i<=9; i++)
{
for (j=1; j<=i; j++)
{
printf ("%d*%d=%d p",i,j,i*j);
}
printf ("\n");
}
return 0;
}

评定成绩等级

#include <stdio.h>
int main(int argc, char *argv[])
{
int score;
printf ("please enter score(score<=10):");
scanf("%d",&score);
if (score==100)
{
score =90;
}
score = score/10;
switch(score)
{
case 9:
printf ("the grade is A\n");
break;
case 8:
printf ("the grade is B\n");
break;
case 7:
printf ("the grade is C\n");
break;
case 6:
printf ("the grade is D\n");
break;
default:
printf ("the grade is E\n");
}
return 0;
}

对调数问题

#include <stdio.h>
int main(int argc, char *argv[])
{
int x,y,z,x1,y1,z1,i,k,n,j=0;
while(1)
{
printf ("please input an integer\n");
scanf("%d",&n);
if (n<=10||n>=100)
{
printf ("data error\n");
continue;
}
else if (n%10==0)
{
printf ("data error\n");
continue;
}
else
{
x=n/10;
y=n%10;
z=10*y+x;
break;
}
}
for (i=11; i<100; i++)
{
if (i%10==0)
continue; //结束本次循环
else
{
x1=i/10;
y1=i%10;
z1=10*y1+1;
//判断是否满足等式条件
if (n+i==z+z1&&n!=z1)
{
printf ("%d+%d=%d+%d\n",n,i,z,z1);
j++;
}
else
continue;
}
}
if(j==0)
printf ("inexistince\n");
return 0;
}

判断润年

#include <stdio.h>
int main(int argc, char *argv[])
{
int year;
printf ("please input the year:\n");
scanf("%d",&year);
if((year%4==0&&year%100!=0)||year%400==0)
printf ("%d is a leap year\n",year);
else
printf ("%d is not a leap year\n",year);
return 0;
}

阶梯问题

#include <stdio.h>
int main(int argc, char *argv[])
{
int i;
for (i=100; i<1000; i++)
{
if(i%2==1&&i%3==2&&i%5==4&&i%6==5&&i%7==0)
printf ("the number of the stairs is %d\n",i);
}
return 0;
}

IP地址形式输出

#include <stdio.h>
int bin_dec(int x,int n) //将而进制转换成十进制
{
if(n==0)
return 1;
return x*bin_dec(x,n-1);
}
int main(int argc, char *argv[])
{
int i;
int ip[4]={0};
char a[33];
printf ("please input binary number:\n");
scanf("%s",a);
for (i=0; i<8; i++)
{
if (a[i]=='1')
{
ip[0]+=bin_dec(2,7-i);
}
}
for (i=8; i<16; i++)
{
if (a[i]=='1')
{
ip[1]+=bin_dec(2,15-i);
}
}
for (i=16; i<24; i++)
{
if (a[i]=='1')
{
ip[2]+=bin_dec(2,23-i);
}
}
for (i=24; i<32; i++)
{
if (a[i]=='1')
{
ip[3]+=bin_dec(2,31-i);
}
if (a[i]=='\0')
{
break;
}
}
printf ("ip:");
printf ("%d.%d.%d.%d\n",ip[0],ip[1],ip[2],ip[3]);
return 0;
}

N进制转换为十进制

#include <stdio.h>
#include <string.h>
main()
{
long t1;
int i,n,t,t3;
char a[100];
printf ("please input a number string:\n");
gets(a); //输入N进制数存到数组a中
strupr(a); //将a中的小写字母转换成大写字母
t3=strlen(a);
t1=0;
printf ("please input n(2or8or16):\n");
scanf("%d",&n);
for (i=0; i<t3; i++)
{
if (a[i]-'0'>=n&&a[i]<'A'||a[i]-'A'+10>=n)//判断输入的数据和进制数是否相等
{
printf ("data error!!");
exit(0); //推出程序
}
if (a[i] >= '0'&&a[i] <= '9') //判断是否为数字
t=a[i]-'0';
else if(n>=11&&(a[i]>='A'&&a[i]<='A'+n-10)) //判断是否为字母o
t=a[i]-'A'+10;
t1=t1*n+t; //求出最终转换成十进制的值
}
printf ("the decimal is %ld\n",t1);
return 0;
}

求同学的平均身高

#include <stdio.h>
float average(float array[],int n)
{
int i;
float aver,sum=0;
for(i=0;i<n;i++)
sum+=array[i];
aver=sum/n;
return(aver);
}
int main(int argc, char *argv[])
{
float average(float array[],int n);
float height[100],aver;
int i,n;
printf ("please input the number of students:\n");
scanf("%d",&n);
printf ("please input student's height:\n");
for(i=0;i<n;i++)
scanf("%f",&height[i]);
printf ("\n");
aver=average(height,n);
printf ("average height is %6.2f\n",aver);
return 0;
}

读取进程中的PEB环境块:

#include <stdio.h>
#include <windows.h>
#include <winternl.h>

typedef NTSTATUS(NTAPI *typedef_NtQueryInformationProcess)(
IN HANDLE ProcessHandle,
IN PROCESSINFOCLASS ProcessInformationClass,
OUT PVOID ProcessInformation,
IN ULONG ProcessInformationLength,
OUT PULONG ReturnLength OPTIONAL
);

PEB Get_PEB(DWORD dwPid)
{
typedef_NtQueryInformationProcess NtQueryInformationProcess = NULL;
PROCESS_BASIC_INFORMATION pbi = { 0 };
RTL_USER_PROCESS_PARAMETERS Param = { 0 };
PEB peb = { 0 };

HANDLE hProcess = ::OpenProcess(PROCESS_ALL_ACCESS, FALSE, dwPid);

// 需要通过 LoadLibrary、GetProcessAddress 从 ntdll.dll 中获取地址
NtQueryInformationProcess = (typedef_NtQueryInformationProcess)::GetProcAddress(
::LoadLibrary("ntdll.dll"), "NtQueryInformationProcess");
if (NULL != NtQueryInformationProcess)
{
// 获取指定进程的基本信息
NTSTATUS status = NtQueryInformationProcess(hProcess, ProcessBasicInformation, &pbi, sizeof(pbi), NULL);
}

// 获取指定进程进本信息结构中的PebBaseAddress
::ReadProcessMemory(hProcess, pbi.PebBaseAddress, &peb, sizeof(peb), NULL);
// 获取指定进程环境块结构中的ProcessParameters, 注意指针指向的是指定进程空间中
// ::ReadProcessMemory(hProcess, peb.ProcessParameters, &Param, sizeof(Param), NULL);

printf("是否被调试: %d \n", peb.BeingDebugged);
return peb;
}

int main(int argc, char * argv[])
{
Get_PEB(GetCurrentProcessId());
system("pause");
return 0;
}