Card game

input/code.c: In function 'main':
input/code.c:20:5: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   20 |     scanf("%d", &n);
      |     ^~~~~~~~~~~~~~~

#include <stdio.h>
#include <stdlib.h>

#define MAX(X, Y) (((X) > (Y)) ? (X) : (Y))

int n;
int *mem;
int *cards;

int opt(int i) {
    if(i<1) return 0;

    if(mem[i] > -1) return mem[i];

    mem[i] = MAX(opt(i-1), opt(i-3) + cards[i]);
    return mem[i];
}

int main() {
    scanf("%d", &n);
    mem = calloc(n, sizeof(int));
    cards = calloc(n, sizeof(int));

    for(int i = 0; i < n; i++)
        mem[i] = -1;

    for (int i = 0; i < n; i++)
        if (scanf("%d", &cards[i]) != 1) return 1;

    printf("%d\n", opt(n-2));

    free(mem);
    free(cards);
    return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED