LeetCode/LeetCode-264.c at master · hello-sources/LeetCode · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
/*************************************************************************
w > File Name: LeetCode-264.c
    > Author: ltw
    > Mail: [email protected]
    > Created Time: Thu 21 May 2020 10:50:44 PM CST
 ************************************************************************/

#define swap(a, b) { \
    __typeof(a) __temp = a; \
    a = b, b = __temp; \
}

typedef struct Heap {
    long long *data;
    int n, size;
} Heap;

Heap *init(int n) {
    Heap *h = (Heap *)malloc(sizeof(Heap));
    h->n = 0;
    h->size = n + 1;
    h->data = (long long *)malloc(sizeof(long long) * h->size);
    return h;
}

int empty(Heap *h) {
    return h->n == 0;
}

#define V(x) h->data[x]

void push(Heap *h, long long val) {
    h->data[++(h->n)] = val;
    int ind = h->n;
    while (ind > 1 && V(ind) < V(ind >> 1)) {
        swap(V(ind), V(ind >> 1));
        ind >>= 1;
    }
    return ;
}

long long top(Heap *h) { return V(1); }

void pop(Heap *h) {
    if (empty(h)) return ;
    V(1) = V(h->n);
    (h->n)--;
    int ind = 1;
    while ((ind << 1) <= h->n) {
        int temp = ind, l = ind << 1, r = ind << 1 | 1;
        if (V(l) < V(temp)) temp = l;
        if (r <= h->n && V(r) < V(temp)) temp = r;
        if (temp == ind) break;
        swap(V(ind), V(temp));
        ind = temp;
    }
    return ;
}

void clear(Heap *h) {
    if (h == NULL) return ;
    free(h->data);
    free(h);
    return ;
}

int nthUglyNumber(int n){
    Heap *h = init(3 * n);
    push(h, 1);
    long long ans = 0;
    while (n--) {
        ans = top(h);
        pop(h);
        if (ans % 5 == 0) {
            push(h, 5 * ans);
        } else if (ans % 3 == 0) {
            push(h, 3 * ans);
            push(h, 5 * ans);
        } else {
            push(h, 2 * ans);
            push(h, 3 * ans);
            push(h, 5 * ans);
        }
    }
    clear(h);
    return ans;
}