# C++ beginner s2-basic

Type

```cpp
int iValue = 10;
bool bValue = true;
string sName = "Jason";
char cValue = 'g';

cout << "Size of int: " << sizeof(unsigned int) << endl;
cout << "Size of short int: " << sizeof(short int) << endl;
```

Precision

```cpp
#include <iomanip>

float fValue = 76.4;
cout << fixed << fValue << endl; // 76.400002
cout << scientific << fValue << endl; // 7.640000e+01

long double lValue = 123.456789876543210;
cout << setprecision(20) << fixed << lValue << endl; // 123.45678987654321190348
```

if else

```cpp
if (iValue == 1) {
    cout << "Adding new record..." << endl;
} else if (iValue == 10) {
    cout << "Deleting record..." << endl;
} else {
    cout << "Invalid option." << endl;
}
```

while

```cpp
int i = 0;

while(i < 5) {
    cout << "Hello " << i << endl;
    i++;
}
```

do while

```cpp
const string password = "hello";
string input;

do {
    cout << "Enter your password > " << flush;
    cin >> input;

    if(input != password) {
        cout << "Access denied." << endl;
    }
} while (input != password);
```

for

```cpp
for (int i = 0; i < 10; i++) {
    cout << "Hello " << i << endl;
}
```

continue / break

```cpp
 for(int i=0; i<5; i++) {
    cout << "i is: " << i << endl;

    if (i == 1) { continue; } // continue & skip "Looping ..."
    if (i == 3) { break; } // break for loop

    cout << "Looping ..." << endl;
 }
```

array

```cpp
int values[3];
values[0] = 88;
values[1] = 123;
values[2] = 7;

int values[] = {4, 7, 3, 4};
int arr_len = sizeof(values)/sizeof(int);
for(unsigned int i=0; i < arr_len; i++) {
    cout << values[i] << " " << flush;
}
```

multi-dim array

```cpp
string animals[][3] = {
    { "fox", "dog", "cat" },
    { "mouse", "squirrel", "parrot" }
};

for(unsigned int i=0; i< sizeof(animals)/sizeof(animals[0]); i++) {
    for(unsigned int j=0; j< sizeof(animals[0])/sizeof(string); j++) {
        cout << animals[i][j] << " " << flush;
    }
    cout << endl;
}
```

switch

```cpp
int value = 4;

switch (value) {
case 4:
    cout << "Value is 4." << endl;
    break;
case 5:
    cout << "Value is 5." << endl;
    break;
default:
    cout << "Unrecognized value." << endl;
}
```


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