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hdu 4893 Wow! Such Sequence!(线段树)

 
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题目链接:hdu 4983 Wow! Such Sequence!

题目大意:就是三种操作
1 k d, 修改k的为值增加d
2 l r, 查询l到r的区间和
3 l r, 间l到r区间上的所以数变成最近的斐波那契数,相等的话取向下取。

解题思路:线段树,对于每个节点新增一个bool表示该节点以下的位置是否都是斐波那契数。

#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <algorithm>

#define lson(x) ((x<<1))
#define rson(x) ((x<<1)|1)

using namespace std;
typedef __int64 ll;

const int maxn = 100005;
const int maxf = 100;
const ll INF = 2000000000000000LL;

int n, m;
ll fib[maxf], fn, num[maxn];

struct maxnode {
    int l, r;
    ll sum;
    bool isfib;

    void set (int l, int r, ll sum, bool isfib) {
        this->l = l;
        this->r = r;
        this->sum = sum;
        this->isfib = isfib;
    }
} node[4 * maxn];

void init () {
    fib[0] = fib[1] = 1;
    for (fn = 2;; fn++) {
        fib[fn] = fib[fn - 2] + fib[fn - 1];
        if (fib[fn] > INF)
            break;
    } 
}

void pushup(int x) {
    int l = lson(x), r = rson(x);

    node[x].isfib = (node[l].isfib && node[r].isfib);
    node[x].sum = node[l].sum + node[r].sum;;
}

void build(int l, int r, int x) {
    node[x].set(l, r, 0, false);

    if (l == r)
        return;

    int mid = (l + r) / 2;

    build(l, mid, lson(x));
    build(mid + 1, r, rson(x));
}

ll find (ll x) {
    int id;
    ll ans = INF;
    for (int i = 0; i < fn; i++) {
        ll k = (fib[i] > x ? fib[i] - x : x - fib[i]);
        if (k < ans) {
            ans = k;
            id = i;
        }
    }
    return fib[id];
}

void add (int k, ll v, int x) {

    if (node[x].l == k && node[x].r == k) {
        node[x].sum += v;
        node[x].isfib = (find(node[x].sum) == node[x].sum ? true : false);
        return;
    }

    int mid = (node[x].l + node[x].r) / 2;
    if (k <= mid)
        add(k, v, lson(x));
    else if (k > mid)
        add(k, v, rson(x));
    pushup(x);
}

void insert(int l, int r, int x) {

    if (node[x].isfib)
        return;

    if (node[x].l == node[x].r) {
        node[x].sum = find(node[x].sum);
        node[x].isfib = true;
        return;
    }

    int mid = (node[x].l + node[x].r) / 2;
    if (l <= mid)
        insert(l, r, lson(x));
    if (r > mid)
        insert(l, r, rson(x));
    pushup(x);
}

ll query(int l, int r, int x) {

    if (node[x].l >= l && node[x].r <= r)
        return node[x].sum;

    int mid = (node[x].l + node[x].r) / 2;

    ll ans = 0;
    if (l <= mid)
        ans += query(l, r, lson(x));
    if (r > mid)
        ans += query(l, r, rson(x));
    return ans;
}

int main() {
    init();

    while (scanf("%d%d", &n, &m) == 2) {
        build(1, n, 1);

        int Q, a, b;
        ll v;

        while (m--) {
            scanf("%d", &Q);
            if (Q == 1) {
                scanf("%d%I64d", &a, &v);
                add(a, v, 1);
            } else if (Q == 2) {
                scanf("%d%d", &a, &b);
                printf("%I64d\n", query(a, b, 1));
            } else {
                scanf("%d%d", &a, &b);
                insert(a, b, 1);
            }
        }
    }
    return 0;
}

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