Lightoj1120线段树扫描线【模板】

算是最基础的线段树扫描线了把。

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注意横坐标区间如果是[1, 3]实际长度是2，维护是两个点而不是3个。

#include<stdio.h>#include<string.h>#include<math.h>#include<queue>#include<vector>#include<map>#include<set>#include<algorithm>#include<list>using namespace std;typedef pair<int,int> PII;typedef long long LL;#define lson l, m, rt<<1#define rson m+1, r, rt<<1|1const int INF = 0x3f3f3f3f;const int Maxn = 33333 + 10;int x[Maxn<<1], n, sum[Maxn<<3], cnt[Maxn<<3], x_num, line_num;LL ans;struct Line{    int l, r, h, s;    Line(){}    Line(int ll, int rr, int hh ,int ss):l(ll), r(rr), h(hh), s(ss){}    bool operator < (const Line &l) const{        return h < l.h;    }}L[Maxn<<1];void build(){    memset(sum, 0, sizeof(sum));    memset(cnt, 0, sizeof(cnt));    x_num = line_num = 0;    ans = 0;}void pushUp(int rt, int l, int r){    if(cnt[rt]) sum[rt] = x[r+1] - x[l];    else if(l == r) sum[rt] = 0;    else sum[rt] = sum[rt<<1] + sum[rt<<1|1];}void update(int L, int R, int s, int l, int r, int rt){    if(L <= l && R >= r){        cnt[rt] += s;        pushUp(rt, l, r);        return;    }    int m = (l+r) >> 1;    if(m >= R) update(L, R, s, lson);    else if(m < L) update(L, R, s, rson);    else{        update(L, m, s, lson);        update(m+1, R, s, rson);    }    pushUp(rt, l, r);}int search(int k){    int l = 1, r = x_num, m;    while(l<=r){        m = (l + r) >> 1;        if(x[m] == k) return m;        else if(k < x[m]) r = m - 1;        else l = m + 1;    }    return -1;}int main(){    int T, cas=1;    scanf("%d", &T);    while(T--){        scanf("%d", &n);        build();        for(int i=0;i<n;i++){            int a, b, c, d;            scanf("%d%d%d%d", &a, &b, &c, &d);            x[++x_num] = a;            x[++x_num] = c;            L[line_num++] = Line(a, c, b, 1);            L[line_num++] = Line(a, c, d, -1);        }        sort(x+1, x+x_num+1);        sort(L, L+line_num);        int temp = 1;        for(int i=2;i<=x_num;i++){            if(x[i] != x[i-1]) x[++temp] = x[i];        }        ans = 0;        x_num = temp;        for(int i=0;i<line_num;i++){            int l = search(L[i].l);            int r = search(L[i].r)-1;            if(!i) update(l, r, L[i].s, 1, x_num, 1);            else{                ans += (LL)sum[1]*(L[i].h - L[i-1].h);                update(l, r, L[i].s, 1, x_num, 1);            }        }        printf("Case %d: %lld\n", cas++, ans);    }    return 0;}