# 29 Numerics library [numerics]

## 29.6 Random number generation [rand]

### 29.6.8 Random number distribution class templates [rand.dist]

#### 29.6.8.2.1 Class template uniform_­int_­distribution[rand.dist.uni.int]

A uniform_­int_­distribution random number distribution produces random integers i, aib, distributed according to the constant discrete probability function

P(i|a,b)=1/(ba+1).

```template<class IntType = int>
class uniform_int_distribution {
public:
// types
using result_type = IntType;
using param_type  = unspecified;

// constructors and reset functions
explicit uniform_int_distribution(IntType a = 0, IntType b = numeric_limits<IntType>::max());
explicit uniform_int_distribution(const param_type& parm);
void reset();

// generating functions
template<class URBG>
result_type operator()(URBG& g);
template<class URBG>
result_type operator()(URBG& g, const param_type& parm);

// property functions
result_type a() const;
result_type b() const;
param_type param() const;
void param(const param_type& parm);
result_type min() const;
result_type max() const;
};```

```explicit uniform_int_distribution(IntType a = 0, IntType b = numeric_limits<IntType>::max()); ```

Requires: ab.

Effects: Constructs a uniform_­int_­distribution object; a and b correspond to the respective parameters of the distribution.

```result_type a() const; ```

Returns: The value of the a parameter with which the object was constructed.

```result_type b() const; ```

Returns: The value of the b parameter with which the object was constructed.