/*int a = 4;*/ 单分支if: if (a > 1) { return 0; } 双分支if: if (a > 1) { return 0; } else { cout<<a<<endl; } 多条件if: if (a < 0) { cout << 0 << endl; } else if (a < 1) { cout << 1 << endl; } else if (a < 2) { cout << 2 << endl; } else { cout << a << endl; } 输入成绩判断考入的大学 int w = 0; cout << "输入您的成绩 "; cin >> w; cout << endl << endl; if (w >= 600) { cout << "考入一本!! "; if (w > 700) cout << "恭喜您考入北大 "; else if (w > 650) cout << "清华" << endl; else cout << "人民大学" << endl; } else if (w >= 500) cout << "考入二本" << endl; else if (w >=400) cout << "考入三本" << endl; else cout << "大专人,大专魂 "; 三只小猪体重 int a, b, c; cout << "输入体重" << endl; cin >> a >> b >> c; if (a > b) { if (b>c) cout << "a最重" << endl; else { if (a > c) cout << "a最重" << endl; else cout << "c最重 "; } } else { if (a> c) cout << "b最重" << endl; else { if (b > c) cout << "b最重" << endl; else cout << "c最重 "; } }
switch语句 int a; cout << "请输入月份 "; cin >> a; switch (a) { case 1: case 3: case 5: case 7: case 8: case 10: case 12: cout << "您输入的月份有三十一天 "; break; case 2: cout << "您输入的月份有28天 "; break; case 4: case 6: case 9: case 11: cout << "您输入的月份有三十天 "; break; default: cout << "输入有错 "; break; }
三目运算符:(a > b? true :false) int a, b; cout << "输入两数 "; cin >> a >> b; cout << "最大的为:" << (a > b ? a : b) << endl;
while语句: int a = 5; int b = 0; while (b == 0) { cout << "b的值为:" << b << endl; b++; }
猜数字游戏:
猜数字的游戏 srand((int)time(0)); int a = rand() % 5 + 1; cout << "请输入一个数:" << endl; int b; int c = 1; cin >> b; while (b != a) { c++; if (b > a) { cout << "输入大了请重新输入" << endl; cin >> b; } else if (b < a) { cout << "输入小了请重新输入" << endl; cin >> b; } } cout << "终于对了,您尝试了" << c << "次" << endl;
do...while语句 至少执行一次 int a =5; do { cout << "好好好 "; a--; } while (a > 0); 水仙花数 int a = 100; do { int b = 0; int c = 0; int d = 0; b = a / 100; c = (a / 10) % 10; d = a % 10; if (b * b * b + c * c * c + d * d * d == a) { cout << " " << a; } a++; } while (a >= 100 && a < 1000);
for循环语句for(表达式1 ;表达式2 ;表达式3) 表达式1可以写在for函数上面,表达式三可以写在函数内部;表达式2一般不省略; int a = 0; for (; a < 5;) { cout << " " << a << endl; a++; } 从一到一百,含⑦或者七的倍数输出,其余略过 int a = 1; for (; a <= 100; a++) { int b, c; b = a % 10;//个位 c = a / 10;//shiwei if (c == 7 || b == 7 || a % 7 == 0) cout << " " << a << endl; } 嵌套循环乘法口诀表 int a = 1; for (; a < 10; a++) { int b = 1; for (; b <= a; b++) { cout << b << "*" << b << "=" << b * b<<" "; } cout << endl; } int c = 9; for (; c >0; c--) { int b =1; for (; b<=c; b++) { cout << b << "*" << b << "=" << b * b << " "; } cout << endl; }
//break跳转语句:跳出 选择结构 或 循环结构 //continue在 循环语句 中跳过未执行的语句开始下一轮循环 //输出奇数 int a = 0; for (; a <= 100; a++) { if (a % 2==0) continue; cout << a << " "; }
//goto语句:破坏可读性;不建议使用 cout << "1" << endl; cout << 2 << endl; goto b; cout << 3 << endl; cout << 4 << endl; b:cout << 5 << endl; cout << 6 << endl;