HDU 5714 (离散化 树状数组)

#include <cstdio>#include <cstring>#include <cmath>#include <algorithm>#include <iostream>#include <map>#include <vector>using namespace std;#define maxn 21111int a[maxn][3], b[maxn][3];int cnt1, cnt2;int c[maxn], x[maxn], Max[maxn];int n;int cnt;int lowbit (int x) {    return x&(-x);}void add (int pos, int num, bool op) {    for (int i = pos; i <= cnt; i += lowbit (i)) {        if (!op) c[i] += num;        else x[i] += num;    }}int sum (int pos, int op) {    int ans = 0;    for (int i = pos; i > 0; i -= lowbit (i)) {        if (!op) ans += c[i];        else            ans += x[i];    }    return ans;}vector <int> num, l1, r1, l2, r2;map <int, int> gg;void init () {    gg.clear ();    sort (num.begin (), num.end ());    int Max = num.size ();    cnt = 1;    for (int i = 0; i < Max; i++) {        if (!i || num[i] != num[i-1]) {            gg[num[i]] = cnt++;        }    }}int solve () {    num.clear (); l1.clear (), l2.clear(), r1.clear (), r2.clear ();    memset (c, 0, sizeof c);    for (int i = 0; i < cnt1; i++) {        int r = a[i][0]+a[i][2], l = a[i][1]-a[i][2];        if (r >= l) {            l1.push_back (l);            r1.push_back (r);            num.push_back (l);            num.push_back (r);        }    }    memset (x, 0, sizeof x);    for (int i = 0; i < cnt2; i++) {        int r = b[i][0]+b[i][2], l = b[i][1]-b[i][2];        if (r >= l) {            l2.push_back (l);            r2.push_back (r);            num.push_back (l);            num.push_back (r);        }    }    init ();    for (int i = 0; i < l1.size (); i++) {        int l = gg[l1[i]], r = gg[r1[i]];        add (l, 1, 0);        add (r+1, -1 , 0);    }    for (int i = 0; i < l2.size (); i++) {        int l = gg[l2[i]], r = gg[r2[i]];        add (l, 1, 1);        add (r+1, -1, 1);    }    Max[1] = x[1];    for (int i = 2; i <= cnt; i++) {        int cur = sum (i, 1);        Max[i] = max (Max[i-1], cur);    }    int ans = 0;    for (int i = 1; i <= cnt; i++) {        ans = max (ans, sum (i, 0) + Max[i]);    }    return ans;}int main () {    //freopen ("in.txt", "r", stdin);    int t, kase = 0;    scanf ("%d", &t);    while (t--) {        scanf ("%d", &n);        printf ("Case #%d:\n", ++kase);        cnt1 = 0, cnt2 = 0;        for (int i = 1; i <= n; i++) {            int x, y, d, op;            scanf ("%d%d%d%d", &x, &y, &d, &op);            if (op == -1) {                a[cnt1][0] = x, a[cnt1][1] = y, a[cnt1][2] = d;                cnt1++;            }            else {                b[cnt2][0] = x, b[cnt2][1] = y, b[cnt2][2] = d;                cnt2++;            }        }        int ans = solve ();        printf ("%d\n", ans);    }    return 0;}