greater_equal in C++

This C++ program implements the greater_equal predicate. The greater_equal predicate is a binary function object which takes two parameters and returns true if first parameter is greater than or equal to the second parameter. We are using this predicate to compare the vectors lexicographically by using lexicographical_compare algorithm and passing greater_equal as the fifth parameter.

Here is the source code of the C++ program which implements the greater_equal predicate. The C++ program is successfully compiled and run on a Linux system. The program output is also shown below.

```
/*
```

 * C++ Program to implement the greater_equal predicate

```
 */
```
```
#include <iostream>
```
```
#include <algorithm>
```
```
#include <vector>
```
```
#include <functional>
```
```
 
```
```
template<class T>
```

struct greater_equal : public std::binary_function<T, T, bool> {

    bool operator() (const T& a, const T& b) const

```
    {
```
```
        return (a >= b);
```
```
    }
```
```
};
```
```
 
```
```
void print(const std::vector <int>& v)
```
```
{
```

    std::vector <int>::const_iterator i;

    for(i = v.begin(); i != v.end(); i++)

```
    {
```
```
        std::cout << *i << " ";
```
```
    }
```
```
    std::cout << std::endl;
```
```
}
```
```
 
```
```
int main()
```
```
{
```
```
    std::vector <int> a(10), b(10);
```
```
    greater_equal<int> x;
```
```
    bool result;
```
```
 
```
```
    for (int i = 0; i < 10 ;i++)
```
```
    {
```
```
        a[i] = i + 1;
```
```
        b[i] = i + 1;
```
```
    }
```
```
    std::cout << "a : ";
```
```
    print(a);
```
```
    std::cout << "b : ";
```
```
    print(b);
```

    // Comparing a and b lexicographically

    result = std::lexicographical_compare(a.begin(), a.end(), b.begin(), b.end(), x);

```
    if(result == true)
```
```
    {
```

        std::cout << "a is lexicographically greater than or equal to b."

```
                  << std::endl;
```
```
    }
```
```
    else
```
```
    {
```

        std::cout << "a is lexicographically smaller than or equal to b."

```
                  << std::endl;
```
```
    }
```
```
}
```

$ a.out
a : 0 1 2 3 4 5 6 7 8 9 
b : 0 1 2 3 4 5 6 7 8 9 
a is lexicographically greater than or equal to b.

Sanfoundry Global Education & Learning Series – 1000 C++ Programs.

If you wish to look at all C++ Programming examples, go to C++ Programs.

« Prev - unary_function Program in C++

» Next - equal_to Predicate in C++

Related Posts: