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A Demonstration of Branching Based on Relational Operators
#include <iostream>
int main()
{
using std::cout;
using std::cin;
int i, i2;
cout << "Enter the score for the Mets: ";
cin >> i;
cout << "\nEnter the score for the Yankees: ";
cin >> i2;
if (i > i2)
cout << "Go i!\n";
if (i < i2)
{
cout << "Go i2!\n";
}
if (i == i2)
{
cout << "A tie?\n";
cout << "Give me the real score for the i2: ";
cin >> i2;
if (i > i2)
cout << "i";
if (i2 > i)
cout << "i2";
if (i2 == i)
cout << "tie!";
}
return 0;
}Create an XOR using the C++ logical operators.
#include <iostream>
#include <cmath>
using namespace std;
int main()
{
bool p, q;
p = true;
q = true;
cout << p << " XOR " << q << " is " <<
( (p || q) && !(p && q) ) << "\n";
p = false;
q = true;
cout << p << " XOR " << q << " is " <<
( (p || q) && !(p && q) ) << "\n";
p = true;
q = false;
cout << p << " XOR " << q << " is " <<
( (p || q) && !(p && q) ) << "\n";
p = false;
q = false;
cout << p << " XOR " << q << " is " <<
( (p || q) && !(p && q) ) << "\n";
return 0;
}1 XOR 1 is 0
0 XOR 1 is 1
1 XOR 0 is 1
0 XOR 0 is 0
Logical operator keywords: and, or, not, not_eq
#include <iostream>
using std::boolalpha;
using std::cout;
using std::endl;
int main()
{
bool a = true;
bool b = false;
int c = 2;
int d = 3;
cout << boolalpha;
cout << "a = " << a << "; b = " << b
<< "; c = " << c << "; d = " << d;
cout << "\n\nLogical operator keywords:";
cout << "\n a and a: " << ( a and a );
cout << "\n a and b: " << ( a and b );
cout << "\n a or a: " << ( a or a );
cout << "\n a or b: " << ( a or b );
cout << "\n not a: " << ( not a );
cout << "\n not b: " << ( not b );
cout << "\na not_eq b: " << ( a not_eq b );
return 0;
}a = true; b = false; c = 2; d = 3
Logical operator keywords:
a and a: true
a and b: false
a or a: true
a or b: true
not a: false
not b: true
a not_eq b: true
Output the results of several variable comparisons.
#include <iostream>
using namespace std;
int main(void)
{
int a = 4, b = 5;
cout << a << " > " << b << " is " << (a > b) << endl;
cout << a << " >= " << b << " is " << (a >= b) << endl;
cout << a << " == " << b << " is " << (a == b) << endl;
cout << a << " <= " << b << " is " << (a <= b) << endl;
cout << a << " < " << b << " is " << (a < b) << endl;
return 0;
}The relational and logical operators
#include <iostream>
using namespace std;
int main() {
int i, j;
bool b1, b2;
i = 10;
j = 11;
if(i < j) cout << "i < j\n";
if(i <= j) cout << "i <= j\n";
if(i != j) cout << "i != j\n";
if(i == j) cout << "this won"t execute\n";
if(i >= j) cout << "this won"t execute\n";
if(i > j) cout << "this won"t execute\n";
b1 = true;
b2 = false;
if(b1 && b2) cout << "this won"t execute\n";
if(!(b1 && b2)) cout << "!(b1 && b2) is true\n";
if(b1 || b2) cout << "b1 || b2 is true\n";
return 0;
}i < j
i <= j
i != j
!(b1 && b2) is true
b1 || b2 is true
Use And operator to connect two boolean expressions
#include <iostream>
int main()
{
int i1, i2;
i1 = 4;
i2 = 2;
if ((i1 != 0) && (i2 != 0))
std::cout << "Both are not zero #1\n";
return (0);
}Both are not zero #1
