BASIC OPERATIONS OF STACK
int isFull ( Stack * stack ) { return stack -> top - 1 == stack -> size ; } int isEmpty ( Stack * stack ) { return stack -> top == -1 ; } void push ( Stack * stack , node * node ) { if ( isFull ( stack ) ) return ; stack -> array [ ++ stack -> top ] = node ; } node * pop ( Stack * stack ) { if ( isEmpty ( stack ) ) return NULL ; return stack -> array [ stack -> top -- ] ; }