免费送气球
http://acm.hdu.edu.cn/contests/contest_showproblem.php?pid=1004&cid=843
C++版本一
https://www.cnblogs.com/kls123/p/10542573.html
題解:
每次1操作會(huì)往序列底加first個(gè)second,first 和 second 都是最大1e9的數(shù)據(jù),每次2操作詢問序列中第first到第second個(gè)數(shù)的和
一開始就感覺有點(diǎn)像線段樹,輸入數(shù)據(jù)太大我們可以離線處理把數(shù)據(jù)離散化下,然后扔到線段樹上,維護(hù)兩個(gè)數(shù)組:
sum: 區(qū)間數(shù)的值的和? num: 區(qū)間數(shù)的數(shù)量和? ,對(duì)于每次詢問的first和second,我們找到第first個(gè)和第second個(gè)分別是哪兩個(gè)數(shù)字,
如果兩個(gè)數(shù)字不相同,那么就先算出分別取了多少個(gè)這兩個(gè)數(shù)字,對(duì)于兩個(gè)數(shù)字中間的數(shù)字和我們可以直接用線段樹區(qū)間求和得到
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感覺應(yīng)該有更簡單的寫法,不過一開始思路就往線段樹上偏了,干脆直接用線段樹寫了。。。。。。
#include<bits/stdc++.h> using namespace std; #define ll long long #define lson l,m,rt<<1 #define rson m+1,r,rt<<1|1 #define mid ll m = (l + r) >> 1 const ll mod = 1000000007; const ll M = 2e5+10; ll sum[M<<2],num[M<<2],b[M],op[M],vis[M ]; struct node{ll x,y; }a[M]; void update(ll p,ll c,ll l,ll r,ll rt){if(l == r){sum[rt] = (sum[rt]+(b[p]*c)%mod)%mod;num[rt] += c;return ;}mid;if(p <= m) update(p,c,lson);else update(p,c,rson);sum[rt] = (sum[rt<<1] + sum[rt<<1|1])%mod;num[rt] = num[rt<<1] + num[rt<<1|1]; }ll ask(ll L,ll R,ll l,ll r,ll rt){ //求區(qū)間[L,R]的區(qū)間和if(L <= l&&R >= r){return sum[rt];}mid;ll ret = 0;if(L <= m) ret = (ret + ask(L,R,lson))%mod;if(R > m) ret = (ret + ask(L,R,rson))%mod;return ret; }ll ask1(ll p,ll l,ll r,ll rt){ //尋找序列中第p個(gè)是那個(gè)數(shù)字if(num[rt] >= p&& num[rt] - vis[r] < p){return r;}mid;if(p <= num[rt<<1]) ask1(p,lson);else ask1(p-num[rt<<1],rson); }ll ask2(ll L,ll R,ll l,ll r,ll rt){ //求區(qū)間[L,R]中有多少個(gè)數(shù)字if(L <= l&&R >= r){return num[rt];}mid;ll ret = 0;if(L <= m) ret += ask2(L,R,lson);if(R > m) ret += ask2(L,R,rson);return ret; }int main() {ll n,cnt = 0;cin>>n;for(ll i = 1;i <= n;i ++){cin>>op[i]>>a[i].x >> a[i].y;if(op[i] == 1) b[++cnt] = a[i].y;}sort(b+1,b+1+cnt);for(ll i = 1;i <= n;i ++){if(op[i] == 1){ll id = lower_bound(b+1,b+1+cnt,a[i].y)-b;update(id,a[i].x,1,cnt,1);vis[id] += a[i].x;}else{ll l = ask1(a[i].x,1,cnt,1);ll r = ask1(a[i].y,1,cnt,1);if(l == r){cout<<(b[l]*((a[i].y-a[i].x+1)%mod))%mod<<endl;}else{ll l = ask1(a[i].x,1,cnt,1);ll r = ask1(a[i].y,1,cnt,1);ll k1 = (((ask2(1,l,1,cnt,1) - a[i].x+1)%mod)*b[l])%mod;ll k2 = (((a[i].y - ask2(1,r-1,1,cnt,1))%mod)*b[r])%mod;ll k = 0;k = ask(l+1,r-1,1,cnt,1);cout<<(k+k1+k2)%mod<<endl;}}} }?
總結(jié)