Integer types
- C++ course
- Beginner
- Lesson 13/116
- 4 min
Learn int, short, long, long long and unsigned types.
Integer types
C++ offers several integer types by size: short (at least 16 bits), int (the basic integer), long (at least 32 bits) and long long (at least 64 bits).
Each type has a signed and unsigned version. signed can hold negative values; unsigned holds only zero and positive but offers twice the range.
The exact size varies by system; for fixed sizes use int32_t, int64_t from the <cstdint> header. For general use int is usually enough.
signed and unsigned
When you write unsigned before a type, it holds only zero and positive values. unsigned int u = 42; is valid; u = -1; gives a compile warning.
signed can hold negative values: signed int s = -5;. By default, types like int and long are signed; writing signed is optional.
Unsigned types have twice the positive range: an 8-bit signed char holds -128..127, unsigned char holds 0..255. For counters that never go negative, unsigned makes sense.
Practice Print three integer types
Inside main, declare an int (value 100), a long (value 1000000) and a long long (value 10000000000). Print each on its own line with std::cout using std::endl.
Starter code
#include <iostream>
int main() {
// Declare int, long and long long
// Print each with std::cout
return 0;
}Sample solution
#include <iostream>
int main() {
// Declare int, long and long long
int small = 100;
long medium = 1000000;
long long large = 10000000000;
// Print each with std::cout
std::cout << small << std::endl;
std::cout << medium << std::endl;
std::cout << large << std::endl;
return 0;
}Expected output
100 1000000 10000000000
Questions and answers
Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.
1 Which is the largest integer type?
- short
- int
- long long Correct answer
- long
Explanation: long long is at least a 64-bit integer type.
2 Large integer
____ large = 10000000000;long long large = 10000000000;Explanation: long long holds very large integers.
3 Match types with ranges
| Term | Meaning |
|---|---|
short |
Small integer |
int |
Basic integer |
long long |
Widest integer |
unsigned |
Positive only |