Tree/BinaryTreeNonRecursivePost.c
int isEmpty(StackNode* S) {
    if (S->next == NULL) {
        return 1;
    }
    else {
        return 0;
    }
}
/**
 * judge stack is or not empty
 * @param S the pointer of stack
 * @return 0 or 1
 */
judge stack is or not empty
@param S the pointer of stack
@return 0 or 1
judge stack is or not empty @param S the pointer of stack @return 0 or 1
int isEmpty(StackNode* S) {
    if (S->next == NULL) {
        return 1;
    }
    else {
        return 0;
    }
}
int isEmpty ( StackNode * S ) { if ( S -> next == NULL ) { return 1 ; } else { return 0 ; } }
judge stack is or not empty
 @param S the pointer of stack
 @return 0 or 1
judge stack is or not empty @param S the pointer of stack @return 0 or 1