iomanip

---

1. Formatting Integer Output

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 12345;
  cout << setw(10) << num; // Output:  12345
  return 0;
}

2. Left-Justifying String Output

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  string str = "Hello";
  cout << setw(10) << left << str; // Output: Hello
  return 0;
}

3. Right-Justifying String Output

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  string str = "Hello";
  cout << setw(10) << right << str; // Output:    Hello
  return 0;
}

4. Centering String Output

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  string str = "Hello";
  cout << setw(10) << center << str; // Output:  Hello 
  return 0;
}

5. Setting Field Width

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 12345;
  cout << setw(10) << num; // Output:  12345
  return 0;
}

6. Truncating Output

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  string str = "Hello World";
  cout << setw(10) << str; // Output: Hello Wor (truncated)
  return 0;
}

7. Inserting Leading Zeros

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setw(10) << setfill('0') << num; // Output: 000000123
  return 0;
}

8. Inserting Leading Spaces

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setw(10) << setfill(' ') << num; // Output:       123
  return 0;
}

9. Formatting Floating-Point Numbers

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  double num = 3.14159;
  cout << fixed << setprecision(2) << num; // Output: 3.14
  return 0;
}

10. Suppressing Scientific Notation

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  double num = 1.23456789e+10;
  cout << fixed << setprecision(2) << num; // Output: 12345678900.00
  return 0;
}

11. Formatting Boolean Values

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  bool b = true;
  cout << boolalpha << b; // Output: true
  return 0;
}

12. Formatting Hexadecimal Values

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << hex << num; // Output: 7b
  return 0;
}

13. Formatting Octal Values

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << oct << num; // Output: 173
  return 0;
}

14. Formatting Money

#include <iostream>
#include <iomanip>
#include <locale>

using namespace std;

int main() {
  double money = 1234.56;
  cout.imbue(locale("")); // Set locale to current locale
  cout << fixed << setprecision(2) << showpoint << money; // Output: $1,234.56
  return 0;
}

15. Formatting Dates

#include <iostream>
#include <iomanip>
#include <ctime>

using namespace std;

int main() {
  time_t t = time(0);
  tm *now = localtime(&t);
  cout << put_time(now, "%c"); // Output: Wed Jun 30 23:59:59 2021
  return 0;
}

16. Formatting Characters

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  char c = 'A';
  cout << setw(10) << left << c; // Output:  A
  return 0;
}

17. Formatting Pointers

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int *p = nullptr;
  cout << setw(10) << left << p; // Output:     0x0
  return 0;
}

18. Formatting User-Defined Types (struct)

#include <iostream>
#include <iomanip>

using namespace std;

struct Point {
  int x;
  int y;
};

ostream& operator<<(ostream& os, const Point& p) {
  os << "(" << p.x << ", " << p.y << ")";
  return os;
}

int main() {
  Point p{1, 2};
  cout << setw(10) << left << p; // Output:  (1, 2)
  return 0;
}

19. Formatting User-Defined Types (class)

#include <iostream>
#include <iomanip>

using namespace std;

class Point {
public:
  int x;
  int y;

  friend ostream& operator<<(ostream& os, const Point& p) {
    os << "(" << p.x << ", " << p.y << ")";
    return os;
  }
};

int main() {
  Point p{1, 2};
  cout << setw(10) << left << p; // Output:  (1, 2)
  return 0;
}

20. Avoiding Left-Padding

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setw(10) << right << noshowpos << num; // Output:    123
  return 0;
}

21. Suppressing Leading Zeros for Float

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  double num = 0.000123;
  cout << fixed << setprecision(3) << num; // Output: 0.000
  return 0;
}

22. Using showpoint for Float

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  double num = 0.000123;
  cout << fixed << setprecision(3) << showpoint << num; // Output: 0.000
  return 0;
}

23. Aligning Characters

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  char c = 'A';
  cout << setw(10) << internal << c; // Output:      A
  return 0;
}

24. Using Copy Delimiter

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 12345;
  cout << setfill('*') << setw(10) << internal << num; // Output: ****12345
  return 0;
}

25. Suppressing Trailing Zeros

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  double num = 123.000;
  cout << fixed << setprecision(3) << nozero << num; // Output: 123
  return 0;
}

26. Using setbase

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setbase(16) << num; // Output: 7b
  return 0;
}

27. Using setfill

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setfill('*') << setw(10) << num; // Output: ****123
  return 0;
}

28. Using left

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setw(10) << left << num; // Output:  123
  return 0;
}

29. Using noshowpos

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setw(10) << right << noshowpos << num; // Output:    123
  return 0;
}

30. Using right

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setw(10) << right << num; // Output:    123
  return 0;
}

31. Using scientific

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  double num = 123.456;
  cout << scientific << num; // Output: 1.234560e+02
  return 0;
}

32. Using setprecision

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  double num = 123.456;
  cout << fixed << setprecision(2) << num; // Output: 123.45
  return 0;
}

33. Using showpoint

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  double num = 0.000123;
  cout << fixed << setprecision(3) << showpoint << num; // Output: 0.000
  return 0;
}

34. Using uppercase

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << uppercase << hex << num; // Output: 7B
  return 0;
}

35. Using ws

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  double num = 123.456;
  cout << ws << num; // Output: 123.456
  return 0;
}

36. Using oct

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << oct << num; // Output: 173
  return 0;
}

37. Using hex

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << hex << num; // Output: 7b
  return 0;
}

38. Using fixed

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  double num = 123.456;
  cout << fixed << num; // Output: 123
  return 0;
}

39. Using boolalpha

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  bool b = true;
  cout << boolalpha << b; // Output: true
  return 0;
}

40. Using flush

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  cout << "Hello" << flush; // Output: Hello
  return 0;
}

41. Using dec

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << dec << num; // Output: 123
  return 0;
}

42. Using copyfmt

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setiosflags(ios::dec) << num; // Output: 123
  return 0;
}

43. Using setbase

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setbase(8) << num; // Output: 173
  return 0;
}

44. Using setw

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setw(10) << num; // Output:  123
  return 0;
}

45. Using internal

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setw(10) << internal << num; // Output:      123
  return 0;
}

46. Using showpos

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setw(10) << right << showpos << num; // Output:    +123
  return 0;
}

47. Using setfill

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << setfill('*') << setw(10) << num; // Output: ****123
  return 0;
}

48. Using setprecision

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  double num = 123.456;
  cout << fixed << setprecision(2) << num; // Output: 123.45
  return 0;
}

49. Using uppercase

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  int num = 123;
  cout << uppercase << hex << num; // Output: 7B
  return 0;
}

50. Using ws

#include <iostream>
#include <iomanip>

using namespace std;

int main() {
  double num = 123.456;
  cout << ws << num; // Output: 123.456
  return 0;
}