What can I do to make my code generate an output? - c

Question

#include <stdio.h>
#include <stdlib.h>
typedef enum TypeTag {
ADD,
SUB,
MUL,
DIV,
ABS,
FIB,
} TypeTag;
typedef struct Node {
TypeTag type;
int value;
struct Node *left;
struct Node *right;
} Node;
#define MAXN 100
int fib[MAXN];
// function to create a new node
Node* makeFunc(TypeTag type) {
Node* newNode = (Node*)malloc(sizeof(Node));
newNode->type = type;
newNode->left = NULL;
newNode->right = NULL;
return newNode;
}
// fibonacci function using dynamic programming
int fibonacci(int n) {
int fib[n+1];
fib[0] = 0;
fib[1] = 1;
for(int i = 2; i <= n; i++) {
fib[i] = fib[i-1] + fib[i-2];
}
return fib[n];
}
// function to calculate the value of a node
int calc(Node* node) {
if (node->type == ADD) {
return calc(node->left) + calc(node->right);
}
else if (node->type == SUB) {
return calc(node->left) - calc(node->right);
}
else if (node->type == MUL) {
return calc(node->left) * calc(node->right);
}
else if (node->type == DIV) {
return calc(node->left) / calc(node->right);
}
else if (node->type == ABS) {
return abs(calc(node->left));
}
else if (node->type == FIB) {
return fibonacci(calc(node->left));
}
return node->value;
}
int main() {
for (int i = 0; i < MAXN; i++) {
fib[i] = -1;
}
Node *add = makeFunc(ADD);
add->left = makeFunc(10);
add->right = makeFunc(6);
Node *mul = makeFunc(MUL);
mul->left = makeFunc(5);
mul->right = makeFunc(4);
Node *sub = makeFunc(SUB);
sub->left = makeFunc(calc(add));
sub->right = makeFunc(calc(sub));
Node *fibo = makeFunc(FIB);
fibo->left = makeFunc(abs(calc(sub)));
fibo->value = fibonacci(calc(fibo->left));
printf("add : %d\n", calc(add));
printf("mul : %d\n", calc(mul));
printf("sub : %d\n", calc(sub));
printf("fibo : %d\n", calc(fibo));
printf("Hello world");
// return 0;
}
I think the problem is coming from the makeFunc function but i am not sure what else to do.I tried to print hello world to see if the problem is from my implementations but it still did not print.
I was trying to solve this problem
{
TypeTag type;
} Node;
typedef enum TypeTag {
...
}
Using this structure, please write a function that returns fibonacci sequence based on the following arithmetic operations (+, -,
*, /) and conditions. The fibonacci function should be implemented using Dynamic Programming.
main()
{
Node *add = (*makeFunc(ADD))(10, 6);
Node *mul = (*makeFunc(MUL))(5, 4);
Node *sub = (*makeFunc(SUB))(mul, add);
Node *fibo = (*makeFunc(SUB))(sub, NULL);
calc(add);
calc(mul);
calc(sub);
calc(fibo)
}
Output
add : 16
mul : 20
sub : -4
fibo : 2

Answer 1

You can't use makeFunc(4) to make the representation of the number 4, because 4 == ABS. You should use a separate type for nodes that represent numbers rather than functions. Then use another function to create nodes of this type.
Another problem is here:
sub->right = makeFunc(calc(sub));
You can't call calc(sub) until after you've filled in both sub->left and sub->right. I'm guessing you meant to use calc(mul).
#include <stdio.h>
#include <stdlib.h>
typedef enum TypeTag {
ADD,
SUB,
MUL,
DIV,
ABS,
FIB,
LIT
} TypeTag;
typedef struct Node {
TypeTag type;
int value;
struct Node *left;
struct Node *right;
} Node;
#define MAXN 100
int fib[MAXN];
// function to create a new node
Node* makeFunc(TypeTag type) {
Node* newNode = (Node*)malloc(sizeof(Node));
newNode->type = type;
newNode->left = NULL;
newNode->right = NULL;
return newNode;
}
Node* makeValue(int value) {
Node *newNode = makeFunc(LIT);
newNode->value = value;
return newNode;
}
// fibonacci function using dynamic programming
int fibonacci(int n) {
int fib[n+1];
fib[0] = 0;
fib[1] = 1;
for(int i = 2; i <= n; i++) {
fib[i] = fib[i-1] + fib[i-2];
}
return fib[n];
}
// function to calculate the value of a node
int calc(Node* node) {
if (node->type == ADD) {
return calc(node->left) + calc(node->right);
}
else if (node->type == SUB) {
return calc(node->left) - calc(node->right);
}
else if (node->type == MUL) {
return calc(node->left) * calc(node->right);
}
else if (node->type == DIV) {
return calc(node->left) / calc(node->right);
}
else if (node->type == ABS) {
return abs(calc(node->left));
}
else if (node->type == FIB) {
return fibonacci(calc(node->left));
}
else if (node->type == LIT) {
return node->value;
}
printf("Invalid node type %d\n", node->type);
exit(1);
}
int main() {
for (int i = 0; i < MAXN; i++) {
fib[i] = -1;
}
Node *add = makeFunc(ADD);
add->left = makeValue(10);
add->right = makeValue(6);
Node *mul = makeFunc(MUL);
mul->left = makeValue(5);
mul->right = makeValue(4);
Node *sub = makeFunc(SUB);
sub->left = makeValue(calc(add));
sub->right = makeValue(calc(mul));
Node *fibo = makeFunc(FIB);
fibo->left = makeValue(abs(calc(sub)));
fibo->value = fibonacci(calc(fibo->left));
printf("add : %d\n", calc(add));
printf("mul : %d\n", calc(mul));
printf("sub : %d\n", calc(sub));
printf("fibo : %d\n", calc(fibo));
printf("Hello world\n");
// return 0;
}