Semicolon at end of 'if' statement

Question

Today, after half an hour of searching for a bug, I discovered that it is possible to put a semicolon after an if statement instead of code, like this:

if(a          


        

Answer 1

Semicolon at the end of,
if(a==b); simply finish the statement in single line which means ignore the result of condition and continue the execution from the next line
This code is useful, on the other hand sometime introduce bug in program, for example,

case 1.

a = 5;
b = 3;
if(a == b);
prinf("a and b are equal");

case 2.

a = 5;
b = 5;
if(a == b);
prinf("a and b are equal");
would print the same output on the screen...