In C plus plus I want to use an if statement so if the word in a char array is lets say hi it will perform an operation but what it does is says undeclared identifier please explain in simple manner?

Answer 1

I don't know what your code looks like since you haven't actually provided any, but the compiler is telling you that you are trying to use an identifier that is not in scope. You may or may not have declared the identifier, but if it is not in scope then it is effectively undeclared. The following example illustrates this:

for(int i=0; i<10; ++i)

std::cout<<i<<std::endl;

i=i+1; // ERROR: Undeclared identifier. i is no longer in scope

To resolve this problem, we must move the declaration of i outside of the loop, thus making it accessible both inside and outside of the loop:

int i;

for(i=0; i<10; ++i)

std::cout<<i<<std::endl;

i=i+1; // OK