/// use recursive algorithm, easy to understand. looks like a tree
int knapsack_rec(int index, int current_size){
if (current_size + weight[index] <= knapsacksize && index < nitems){
return max(value[index] + knapsack_rec(index + 1, current_size + weight[index]),
knapsack_rec(index + 1, current_size));
}
return 0;
}
int main () {
int i;
Tab = (int *) malloc ((M+1) * sizeof(int));
/* inizializzazione tabella */
for(i=0;i<=M;i++)
Tab[i] = -1;
printf("\n---------------------------\n- LISTA OGGETTI -\n---------------------------\n");
printf(" OGGETTO VALORE\t SPAZIO\n");
for(i=0;i<N;i++)
printf("\t%c\t\t %2d\t\t%2d\n",O[i].name,O[i].v,O[i].s);
knapsack_rec(M);
printf("\nIl massimo valore ottenuto e' %d\n",knapsack_din(M));
printf("\nNumero di ricorsioni con knapsack_rec = %d\n",count_rec);
printf("Numero di ricorsione con knapsack_din = %d\n",count_din);
printf("\n---------------------------\n- LISTA OGGETTI SCELTI -\n---------------------------\n");
printf(" OGGETTO VALORE\t SPAZIO\n");
/* for(i=M; i >= 1;i-O[indexes[i]].s)
printf(" %c\t%2d\t%2d\n",O[indexes[i]].name,O[indexes[i]].v,O[indexes[i]].s);*/
i=M;
while(i)
{
printf("\t%c\t\t %2d\t\t%2d\n",O[indexes[i]].name,O[indexes[i]].v,O[indexes[i]].s);
i=i-O[indexes[i]].s;
}
return 0;
}
int knapsack_rec(int r){
int i,t,max = 0;
for(i=0;i<N;i++)
{
count_rec++;
if((r - O[i].s) >= 0)
if( (t = O[i].v + knapsack_rec((r - O[i].s))) > max)
max = t;
}
return max;
}
int main()
{
printf ("1. rec max value = %d\n", knapsack_rec(0, 0));
printf ("2. bru max value = %d\n", knapsack_bruteforce());
printf ("3. dyn max value = %d\n", knapsack_dynamic());
memset(dynamic_tab_rec, -1, sizeof(dynamic_tab_rec));
printf ("4. dre max value = %d\n", knapsack_dynamic_rec(nitems, knapsacksize));
return 0;
}