持续更新题目
一、洛谷P1384无聊的数列(传送门)
重点注释:不管update还是query都需要先push_down再做(暂时没有反例,以后想到再写)
#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
const int N = 1e5+10;
int n, m, a[N], tag[N<<2], t[N<<2];
int q, x, ll, rr, k, d;
// int MAX(int x, int y){return x>y?x:y;}
void PUSH_UP(int root, int lson, int rson)
{
t[root] = t[lson]+t[rson];
}
void PUSH_DOWN(int root, int lson, int rson, int ln, int rn)
{
if (tag[root]){
t[lson] += tag[root]*ln;
t[rson] += tag[root]*rn;
tag[lson] += tag[root];
tag[rson] += tag[root]; //错误×1
tag[root] = 0;
}
}
void BUILD(int root, int l, int r)
{
if (l == r){
t[root] = a[l];
return;
}
int mid = (l+r)>>1;
int lson = root<<1;
int rson = lson|1;
BUILD(lson, l, mid);
BUILD(rson, mid+1, r);
PUSH_UP(root, lson, rson);
}
void INTERVAL_UPDATE(int root, int l, int r, int L, int R, int X)
{
if (L <= l && r <= R){
t[root] += X*(r-l+1);
tag[root] += X;
return;
}
int mid = (l+r)>>1;
int lson = root<<1;
int rson = lson|1;
PUSH_DOWN(root, lson, rson, mid-l+1, r-mid); //玄学错误,update也要push_down
if (R >= l && L <= mid) INTERVAL_UPDATE(lson, l, mid, L, R, X);
if (R >= mid+1 && L <= r) INTERVAL_UPDATE(rson, mid+1, r, L, R, X);
PUSH_UP(root, lson, rson);
}
int QUERY(int root, int l, int r, int L, int R)
{
if (L <= l && r <= R)
return t[root];
int mid = (l+r)>>1;
int lson = root<<1;
int rson = lson|1;
int tmp = 0;
PUSH_DOWN(root, lson, rson, mid-l+1, r-mid);
if (R >= l && L <= mid) tmp += QUERY(lson, l, mid, L, R);
if (R >= mid+1 && L <= r) tmp += QUERY(rson, mid+1, r, L, R);
return tmp;
}
int main()
{
scanf("%d%d", &n, &m);
for (int i = 1; i <= n; i++)
scanf("%d", &a[i]);
for (int i = n; i >= 1; i--)
a[i] = a[i]-a[i-1];
BUILD(1, 1, n);
memset(tag, 0, sizeof(tag));
for (int i = 1; i <= m; i++){
scanf("%d", &q);
if (q == 1){
scanf("%d%d%d%d", &ll, &rr, &k, &d);
INTERVAL_UPDATE(1, 1, n, ll, ll, k);
if (ll < rr) INTERVAL_UPDATE(1, 1, n, ll+1, rr, d);
if (rr < n) INTERVAL_UPDATE(1, 1, n, rr+1, rr+1, -(k+(rr-ll)*d));
}
if (q == 2){
scanf("%d", &x);
printf("%d\n", QUERY(1, 1, n, 1, x));
}
}
return 0;
}
二、洛谷P1607庙会班车(传送门)
算是线段树+线段覆盖吧,板子打出来了怎么魔改都无所畏惧
重点备注:变量名尽量不要变
数组:t[N<<2](线段树),lazy[N<<2](懒标记)
三个节点:root,lson,rson
传送参数:l,r,mid(小写是当前区间),L,R,X(大写是需要修改或查询的区间)
#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
const int N = 2e4+10;
const int K =5e4+10;
int k, n, c, ans;
struct NODE{
int l, r, m;
}a[K];
int t[N<<2], lazy[N<<2];
bool cmp(NODE x, NODE y)
{
if (x.r != y.r)
return x.r < y.r;
if (x.l != y.l)
return x.l > y.l;
return x.m > y.m;
}
int MAX(int x, int y){return x>y?x:y;}
void PUSH_UP(int root, int lson, int rson)
{
t[root] = MAX(t[lson], t[rson]);
}
void PUSH_DOWN(int root, int lson, int rson)
{
if (lazy[root]){
lazy[lson] += lazy[root];
lazy[rson] += lazy[root];
t[lson] += lazy[root];
t[rson] += lazy[root];
lazy[root] = 0;
}
}
void UPDATE(int root, int l, int r, int L, int R, int X)
{
if (L <= l && r <= R){
t[root] += X;
lazy[root] += X;
return;
}
int lson = root<<1;
int rson = lson|1;
int mid = (l+r)>>1;
PUSH_DOWN(root, lson, rson);
if (L <= mid) UPDATE(lson, l, mid, L, R, X);
if (mid < R) UPDATE(rson, mid+1, r, L, R, X);
PUSH_UP(root, lson, rson);
}
int QUERY(int root, int l, int r, int L, int R)
{
if (L <= l && r <= R)
return t[root];
int lson = root<<1;
int rson = lson|1;
int mid = (l+r)>>1;
int tmp = 0;
PUSH_DOWN(root, lson, rson);
if (L <= mid) tmp = MAX(tmp, QUERY(lson, l, mid, L, R));
if (mid < R) tmp = MAX(tmp, QUERY(rson, mid+1, r, L, R));
return tmp;
}
int main()
{
scanf("%d%d%d", &k, &n, &c);
for (int i = 1; i <= k; i++)
scanf("%d%d%d", &a[i].l, &a[i].r, &a[i].m), a[i].r--;
sort(a+1, a+k+1, cmp);
ans = 0;
for (int i = 1; i <= k; i++){
int rem = c-QUERY(1, 1, n, a[i].l, a[i].r);
if (rem > 0){
if (a[i].m > rem){
ans += rem;
UPDATE(1, 1, n, a[i].l, a[i].r, rem);
}
else{
ans += a[i].m;
UPDATE(1, 1, n, a[i].l, a[i].r, a[i].m);
}
}
//cout << a[i].l << " " << a[i].r << " " << ans << endl;
}
printf("%d", ans);
return 0;
}