Basic functionality.md (1728B)
1 +++ 2 title = 'Basic functionality' 3 +++ 4 # Basic functionality 5 ## Variables 6 ```cpp 7 int inch; 8 bool answer=true; 9 ``` 10 11 ## Fundamental types 12 - integral: boolean (bool), character (char), integer (int) 13 - arithmetic: floating-point (double), integral types 14 - user-defined types: enumeration (enum) and classes 15 - absence of information (void) 16 17 from these, you can construct: 18 - pointer types (int*, char*,…) 19 - arrays (int[], char[], …) 20 - reference (double&), data structures 21 22 ## Operators 23 - arithmetic: +, -, /, *, % 24 - comparison: ==, !=, <, >, <=, >= 25 - ‘put to’: << 26 - ‘get from’: >> — type accepted depends on the right-hand operand 27 28 ## Tests (conditionals) 29 ```cpp 30 // simple function that asks user to proceed 31 bool accept() { 32 cout << “Do you want to proceed (yN)?\n”; 33 char answer=0; 34 cin >> answer; 35 36 if (answer == ‘y’) return true; 37 return false; 38 } 39 40 // more complex function, with a switch statement 41 bool accept2() { 42 cout << “Do you want to proceed (yN)?\n”; 43 char answer=0; 44 cin >> answer; 45 switch (answer) { 46 case ‘y’: 47 return true; 48 case ’n’: 49 return false; 50 default: 51 cout << “Whatever, it’s a no.\n”; 52 return false; 53 } 54 } 55 ``` 56 57 ## Loops 58 ```cpp 59 while (condition) { 60 // execute code 61 // opt. increment iterator 62 } 63 64 for (int i=0; i<10; i++) { 65 // execute code 66 } 67 ``` 68 69 ## Pointers & arrays 70 - array declaration: 71 ```cpp 72 char v[10]; // array of 10 chars, with 0 as lower bound 73 ``` 74 - pointer declaration: 75 ```cpp 76 char* p; // pointer to a char element 77 ``` 78 - setting a pointer: 79 ```cpp 80 p = &v[3]; // p points to address of index 3 of array v 81 ```