P3130 [USACO15DEC]计数haybalesCounting Haybales
P3130 [USACO15DEC]计数haybalesCounting Haybales
1)给定一段连续的田地,给每一个田地都增加一些新的草包。
2)给定一段连续的田地,找出草包最少的田地有多少草包。
3)给定一段连续的田地,统计一共有多少草包。
错误日志: \(pushdown\) 时记录懒标记用了 \(int\) , 下次(在没有把握的情况下)应全部替换
Solution
线段树, 懒标记, 靠前练手
Code
#include<iostream>
#include<cstdio>
#include<queue>
#include<cstring>
#include<algorithm>
#include<climits>
#define LL long long
using namespace std;
LL RD(){
LL out = 0,flag = 1;char c = getchar();
while(c < '0' || c >'9'){if(c == '-')flag = -1;c = getchar();}
while(c >= '0' && c <= '9'){out = out * 10 + c - '0';c = getchar();}
return flag * out;
}
const LL maxn = 400019;
LL num, na;
LL v[maxn];
#define lid (id << 1)
#define rid (id << 1) | 1
struct seg_tree{
LL l, r;
LL min, sum, lazy;
}tree[maxn << 2];
void pushup(LL id){
tree[id].sum = tree[lid].sum + tree[rid].sum;
tree[id].min = min(tree[lid].min, tree[rid].min);
}
void build(LL id, LL l, LL r){
tree[id].l = l, tree[id].r = r;
if(l == r){
tree[id].min = tree[id].sum = v[l];
return ;
}
LL mid = (l + r) >> 1;
build(lid, l, mid), build(rid, mid + 1, r);
pushup(id);
}
void pushdown(LL id){
if(tree[id].lazy != 0){
LL val = tree[id].lazy;
tree[lid].sum += val * (tree[lid].r - tree[lid].l + 1);
tree[rid].sum += val * (tree[rid].r - tree[rid].l + 1);
tree[lid].min += val;
tree[rid].min += val;
tree[lid].lazy += val;
tree[rid].lazy += val;
tree[id].lazy = 0;
}
}
void update(LL id, LL val, LL l, LL r){
pushdown(id);
if(tree[id].l == l && tree[id].r == r){
tree[id].lazy += val;
tree[id].sum += val * (tree[id].r - tree[id].l + 1);
tree[id].min += val;
return ;
}
LL mid = (tree[id].l + tree[id].r) >> 1;
if(mid < l)update(rid, val, l, r);
else if(mid >= r)update(lid, val, l, r);
else update(lid, val, l, mid), update(rid, val, mid + 1, r);
pushup(id);
}
LL get_sum(LL id, LL l, LL r){
pushdown(id);
if(tree[id].l == l && tree[id].r == r){
return tree[id].sum;
}
LL mid = (tree[id].l + tree[id].r) >> 1;
if(mid < l)return get_sum(rid, l, r);
else if(mid >= r)return get_sum(lid, l, r);
else return get_sum(lid, l, mid) + get_sum(rid, mid + 1, r);
}
LL get_min(LL id, LL l, LL r){
pushdown(id);
if(tree[id].l == l && tree[id].r == r){
return tree[id].min;
}
LL mid = (tree[id].l + tree[id].r) >> 1;
if(mid < l)return get_min(rid, l, r);
else if(mid >= r)return get_min(lid, l, r);
else return min(get_min(lid, l, mid), get_min(rid, mid + 1, r));
}
int main(){
num = RD(), na = RD();
for(LL i = 1;i <= num;i++)v[i] = RD();
build(1, 1, num);
char cmd;
while(na--){
cin>>cmd;
LL l = RD(), r = RD();
if(cmd == 'M')printf("%lld\n", get_min(1, l, r));
else if(cmd == 'S')printf("%lld\n", get_sum(1, l, r));
else{
LL val = RD();
update(1, val, l, r);
}
}
return 0;
}