逻辑运算符
bool flag = true;
cout << !flag << endl;
cout << !!flag << endl;
bool flag1 = false;
bool flag2 = true;
bool flag3;
flag3 = flag && flag1;
cout << flag3 << endl;
flag3 = flag || flag2;
cout << flag3 << endl;
flag3 = flag && flag2;
cout << flag3 << endl;
flag3 = flag || flag1;
cout << flag3 << endl;
条件语句的运用
int a, b, c;
a = b = c = 0;
cout << "请分别输入三只小猪的体重：";
cin >> a >> b >> c;
if (a > b)
{
if (a < c)
{
cout << "c 最重\n";
}
else if (a > c)
{
cout << "a 最重\n";
}
else
{
cout << "a 与 c 都最重\n";
}
}
else if (a == b)
{
if (a < c)
{
cout << "c 最重\n";
}
else if (a > c)
{
cout << "a 与 b 最重\n";
}
else
{
cout << "a 、b 与 c 一样重\n";
}
}
else
{
if (b < c)
{
cout << "c 最重\n";
}
else if (b > c)
{
cout << "b 最重\n";
}
else
{
cout << "a 与 c 都最重\n";
}
}三目运算符
int a, b, c;
a = 10, b = 15, c = 0;
c = a > b ? a : b;
cout << c << endl;
//比较a和b后赋值
(a > b ? a : b) = 100;
cout << a << " " << b << endl;switch语句
int score = 0;
cin >> score;
switch (score)
{
case 10:
cout << "这部电影是经典电影";
break;
case 9:
cout << "这部电影是经典电影";
break;
case 8:
cout << "不错的电影";
break;
case 7:
cout << "不错的电影";
break;
case 6:
cout << "电影一般般";
break;
default:
cout << "电影是烂片";
break;
}
cout << endl;猜数字代码while方式
// 添加随机数种子，利用当前系统时间生成随机数
// 防止每次随机数都一样
srand((unsigned int)time(NULL));
int t = rand()%100 + 1;
cout << t << endl;
int num = -1;
while (1)
{
cin >> num;
if (num == t)
{
cout << "恭喜你猜对了!\n";
break;
}
else if (num < t)
{
cout << "猜小了\n";
}
else
{
cout << "猜大了\n";
}
}猜数字do while()方式
// 添加随机数种子，利用当前系统时间生成随机数
// 防止每次随机数都一样
srand((unsigned int)time(NULL));
int t = rand()%100 + 1;
cout << t << endl;
int num = -1;
int flag = 1;
do
{
cin >> num;
if (t == num)
{
cout << "恭喜你猜对了!\n";
flag = 0;
}
else if (num < t)
{
cout << "猜小了\n";
}
else
{
cout << "猜大了\n";
}
} while (flag); // 条件为假时退出循环do while解决水仙花数-1
//水仙花数：3位数的数字个十百上的数字3次幂之和等于本身
int num = 0;
cin >> num;
int tmp = 0, num2 = 0;
num2 = num;
int i = 3;
do
{
tmp += pow(num % 10,3);
num /= 10;
} while (--i);
cout << endl;
if (num2 == tmp)
{
cout << "是水仙花数";
}
else
{
cout << "不是水仙花数";
}
cout << endl;do while解决水仙花数-2
//水仙花数：3位数的数字个十百上的数字3次幂之和等于本身
int num = 100;
do
{
int a, b, c;
a = num % 10;
b = num / 10 % 10;
c = num / 100;
int num2 = a * a * a + b * b * b + c * c * c;
if (num2 == num)
{
cout << num << "\t";
}
num++;
} while (num<1000);
cout << endl;100以内翘7
int i;
for (i = 1; i <= 100; i++)
{
cout << i;
if (i / 10 == 7 || i % 7 == 0 || i % 10 == 7) // 十位有7、7的倍数、个位有7
{
cout << ", 敲桌子\n";
}
}数组地址
int arr[] = { 1,45,63,64,52 };
char ch[] = "fhlgalf";
cout << sizeof(ch) << endl;
cout << sizeof(arr) << endl;
cout << sizeof(arr) / 4 << endl;
cout << (int)arr << " " << (int)&arr[1] << endl;逆置数组元素
int arr[] = { 5,2,3,9,10,7 };
int endArr = sizeof(arr) / sizeof(arr[0]) - 1;
int start = 0;
while (start<endArr)
{
int temp = arr[start];
arr[start++] = arr[endArr];
arr[endArr--] = temp;
}
for (int i = 0; i < start + endArr + 1; i++)
{
cout << i << " " << arr[i] << endl;
}
/*for (; start < endArr; start++, endArr--)
{
int temp = arr[start];
arr[start] = arr[endArr];
arr[endArr] = temp;
cout << start << " " << endArr << endl;
}
cout << endl;
for (int i = 0; i < start + endArr + 1; i++)
{
cout << i << " " << arr[i] << endl;
}
cout << endl;*/冒泡排序
int arr[6] = { 5,2,3,9,10,7 };
int endArr = sizeof(arr) / sizeof(arr[0]) - 1;
int start = 0;
/*for (int i = 0; i < 6; i++)
{
for (int j = i; j < 5; j++) // j<5，j+1不超过数组长度
{
if (arr[j] > arr[j + 1])
{
int temp = arr[j];
arr[j] = arr[j + 1];
arr[j + 1] = temp;
}
}
}*/
for (int i = 0; i < 6 - 1; i++) //6-1表示需要排序的次数
{
for (int j = 0; j < 6 - 1 - i; j++) //6-1-i表示需要每轮比较后需要比较的个数
{
if (arr[j] > arr[j + 1])
{
int temp = arr[j];
arr[j] = arr[j + 1];
arr[j + 1] = temp;
}
}
}
for (int i = 0; i < 6; i++)
{
cout << arr[i] << '\t';
}
cout << endl;
