Relational Operators on STL Array in C++
Last Updated :
11 Jul, 2025
The article illustrates the working of the different relational operator on the
array STL. The
equality comparison ( == ) is performed by comparing the elements sequentially using operator ( == ), stopping at the first mismatch.
The
less-than comparison ( < ) or
greater-than comparison ( > ) behaves as if using algorithm lexicographical_compare, which compares the elements sequentially using operator () in a reciprocal manner (i.e., checking both a<b and b<a) and stopping at the first occurrence.
The implementation of relational operators on the array help us to compare between the data stored in different arrays.
Equivalent operators : Here are some operators whose work is same.
(a != b) is equivalent to !(a == b)
(a > b) equivalent to (b < a)
(a <= b) equivalent to !(b < a)
Time Complexity : The time complexity of the above operation is
O(n) where n is the size of the array.
Below is the code to illustrate the working of relational operators on array
Program 1: Relational Operator Comparison
CPP
// array comparisons using relational operators
#include <bits/stdc++.h>
using namespace std;
int main()
{
// declaration of array
array<int, 5> a = { 1, 2, 3, 4, 5 };
array<int, 5> b = { 1, 2, 3, 4, 5 };
array<int, 5> c = { 5, 4, 3, 2, 1 };
if (a >= b) {
cout << "a is greater than equal to b\n";
}
else {
cout << "a is neither greater than nor equal to b\n";
}
if (b < c) {
cout << "b is less than c\n";
}
else {
cout << "b is not lesser than c\n";
}
if (a >= c) {
cout << "a is greater than equal to c\n";
}
else {
cout << "a is neither greater than nor equal to c\n";
}
return 0;
}
Output :
a is greater than equal to b
b is less than c
a is neither greater than nor equal to c
Program 2: Relational Operator Equality
CPP
// CPP program to check for array qualities.
#include <bits/stdc++.h>
using namespace std;
int main()
{
// declaration of array
array<char, 5> a = { 'a', 'b', 'c', 'd', 'e' };
array<char, 5> b = { 'e', 'd', 'c', 'b', 'a' };
array<char, 5> c = { 'a', 'b', 'c', 'd', 'e' };
if (a == b) {
cout << "a is equal to b\n";
}
else {
cout << "a is not equal to b\n";
}
if (b != c) {
cout << "b is not equal to c\n";
}
else {
cout << "b is equal to c\n";
}
if (a == c) {
cout << "a is equal to c\n";
}
else {
cout << "a is not equal to c\n";
}
return 0;
}
Output :
a is not equal to b
b is not equal to c
a is equal to c
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