营业额统计

Posted 2022-11-09 liuzz-20180701

题目描述

思路

代码

#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <ctime>
#define min(a, b) ((a) < (b) ? a : b)

const int MAX = (1<<15) + 5;
int n, m, tot, rt, inf = 0x3f3f3f3f;
long long ans;
struct Node 
    int lc, rc, cnt, size, key, pri;
    #define lc(x) t[x].lc
    #define rc(x) t[x].rc
    #define cnt(x) t[x].cnt
    #define size(x) t[x].size
    #define key(x) t[x].key
    #define pri(x) t[x].pri
 t[MAX];

void update(int &r)  size(r) = size(lc(r)) + size(rc(r)) + cnt(r); 

void zig(int &r) 
    int s = lc(r);
    lc(r) = rc(s);
    rc(s) = r;
    size(s) = size(r);
    update(r);
    r = s;


void zag(int &r) 
    int s = rc(r);
    rc(r) = lc(s);
    lc(s) = r;
    size(s) = size(r);
    update(r);
    r = s;


void insert(int &r, int k) 
    if (!r) 
        r = ++tot;
        cnt(r) = size(r) = 1;
        pri(r) = rand(), key(r) = k;
        return;
     else ++size(r);
    if (k == key(r)) ++cnt(r);
    else if(k < key(r)) 
        insert(lc(r), k);
        if (pri(lc(r)) < pri(r)) zig(r);
     else 
        insert(rc(r), k);
        if (pri(rc(r)) < pri(r)) zag(r);
    


void delt(int &r, int k) 
    if (k == key(r)) 
        if (cnt(r) >= 2) cnt(r)--, size(r)--;
        else if (!lc(r) || !rc(r)) r = lc(r) + rc(r);
        else if (pri(lc(r)) < pri(r)) zag(r), delt(r, k);
        else zig(r), delt(r, k);
        return;
    
    if (k < key(r)) delt(lc(r), k);
    else delt(rc(r), k);


int queryPre(int k) 
    int r = rt, res = inf;
    while (r) 
        if (key(r) <= k) res = key(r), r = rc(r);
        else r = lc(r);
    
    return res;


int queryNxt(int k) 
    int r = rt, res = inf;
    while (r) 
        if (key(r) > k) res = key(r), r = lc(r);
        else r = rc(r);
    
    return res;


int queryKth(int k) 
    int r = rt, res = inf;
    while (r) 
        if (size(lc(r)) < k && size(lc(r)) + cnt(r) >= k) return  key(r);
        else if (size(lc(r)) >= k) r = lc(r);
        else k -= size(lc(r)) + cnt(r), r = rc(r); 
    
    return res;


int queryRand(int k) 
    int r = rt, res = 0;
    while (r) 
        if (k == key(r)) return size(lc(r)) + cnt(r) + 1;
        else if (k < key(r)) r = lc(r);
        else res += size(lc(r)) + cnt(r), r = rc(r);
    
    return res;


inline int read() 
    int s = 0, f = 1;
    char ch = getchar();
    while(ch < '0' || ch > '9') 
        if (ch == '-') f = -1;
        ch = getchar();
    
    while (ch >= '0' && ch <= '9') s = s * 10 + ch - '0', ch = getchar();
    return s * f;

void write(long long x) 
    if (x > 9) write(x / 10);
    putchar(x % 10 + '0');

int main() 
    srand(time(NULL));
    n = read(), m = read();
    ans = m;
    insert(rt, m);
    for (int i = 2, j; i <= n; ++i) 
        j = read();
        int a = queryPre(j), b = queryNxt(j);
        // printf("pre:%d nxt:%d ", a, b);
        ans += min(abs(j - a), b - j);
        // printf("ans: %d\n", ans);
        insert(rt, j);
    
    write(ans);
    return 0;