hdoj 1698 Just a Hook

类型：一维线段树

来源：2008 “Sunline Cup” National Invitational Contest

题目：线段更新【颜色下移】，求区间最大值

// hdoj 1698 Just a Hook// wa ac 437MS1416K#include <iostream>#include <cstdio>#include <cstring>using namespace std;#define FOR(i,a,b) for(i = (a); i < (b); ++i)#define FORE(i,a,b) for(i = (a); i <= (b); ++i)#define CLR(a,b) memset(a,b,sizeof(a))const int MAXN = 100000;const int INF = 0x7f7f7f7f;int cas, n, sum, m;int tree[MAXN * 3];void build(int root, int l, int r) {    if(l == r) {        tree[root] = 1;        return ;    }    int mid = (l + r) >> 1;    build(root << 1, l, mid);    build(root << 1 | 1, mid + 1, r);}void insert(int root, int l, int r, int x1, int x2, int col) {    if(l == x1 && r == x2) {        tree[root] = col;        return ;    }    if(tree[root] != 0) {        tree[root << 1] = tree[root << 1 | 1] = tree[root];        tree[root] = 0;    }    int mid = (l + r) >> 1;    if(mid >= x2)        insert(root << 1, l, mid, x1, x2, col);    else if(mid < x1)        insert(root << 1 | 1, mid + 1, r, x1, x2, col);    else {        insert(root << 1, l, mid, x1, mid, col);        insert(root << 1 | 1, mid + 1, r, mid + 1, x2, col);    }}void cal(int root, int l, int r, int x1, int x2) {    int i;    if(l == x1 && r == x2 && tree[root] != 0) {        FORE(i, l, r)            sum += tree[root];        return ;    }    int mid = (l + r) >> 1;    if(mid >= x2)        cal(root << 1, l, mid, x1, x2);    else if(mid < x1)        cal(root << 1 | 1, mid + 1, r, x1, x2);    else {        cal(root << 1, l, mid, x1, mid);        cal(root << 1 | 1, mid + 1, r, mid + 1, x2);    }}int main(){    int i, a, b, c, d;    int nnn = 1;    scanf("%d", &cas);    while(cas--) {        CLR(tree, 0);        scanf("%d", &n);        build(1, 1, n);        scanf("%d", &c);        FOR(i, 0, c) {            scanf("%d %d %d", &a, &b, &d);            insert(1, 1, n, a, b, d);        }        sum = 0;        cal(1, 1, n, 1, n);        printf("Case %d: The total value of the hook is %d.\n", nnn++, sum);    }    return 0;}