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poj3511--A Simple Problem with Integers(线段树求和)
Time Limit: 5000MS | Memory Limit: 131072K | |
Total Submissions: 60441 | Accepted: 18421 | |
Case Time Limit: 2000MS |
Description
You have N integers, A1, A2, ... , AN. You need to deal with two kinds of operations. One type of operation is to add some given number to each number in a given interval. The other is to ask for the sum of numbers in a given interval.
Input
The first line contains two numbers N and Q. 1 ≤ N,Q ≤ 100000.
The second line contains N numbers, the initial values of A1, A2, ... , AN. -1000000000 ≤ Ai ≤ 1000000000.
Each of the next Q lines represents an operation.
"C a b c" means adding c to each of Aa, Aa+1, ... , Ab. -10000 ≤ c ≤ 10000.
"Q a b" means querying the sum of Aa, Aa+1, ... , Ab.
Output
You need to answer all Q commands in order. One answer in a line.
Sample Input
10 5 1 2 3 4 5 6 7 8 9 10 Q 4 4 Q 1 10 Q 2 4 C 3 6 3 Q 2 4
Sample Output
4 55 9 15
Hint
将一段的值增加c 求一段的和
将线段树的每一段表示它代表的那一段的和,统计结果时,要记录一段的所有的父节点的和,对该段会有影响
#include <cstdio> #include <cstring> #include <algorithm> using namespace std; #define maxn 100000 #define LL __int64 #define lmin 1 #define rmax n #define lson l,(l+r)/2,rt<<1 #define rson (l+r)/2+1,r,rt<<1|1 #define root lmin,rmax,1 #define now l,r,rt #define int_now LL l,LL r,LL rt LL cl[maxn<<2] , lazy[maxn<<2]; void push_up(int_now) { cl[rt] = cl[rt<<1] + cl[rt<<1|1] + (r-l+1)*lazy[rt] ; } void push_down(int_now) { } void creat(int_now) { cl[rt] = lazy[rt] = 0 ; if(l != r) { creat(lson); creat(rson); push_up(now); } else scanf("%I64d", &cl[rt]); } void update(LL ll,LL rr,LL x,int_now) { if( ll > r || rr < l ) return ; if( ll <= l && r <= rr ) { lazy[rt] += x ; cl[rt] += (r-l+1)*x ; return ; } update(ll,rr,x,lson); update(ll,rr,x,rson); push_up(now); } LL query(LL ll,LL rr,int_now,LL add) { if( ll > r || rr < l ) return 0; if( ll <= l && r <= rr ) return cl[rt] + ( r-l+1 )*add ; push_down(now); return query(ll,rr,lson,add+lazy[rt]) + query(ll,rr,rson,add+lazy[rt]) ; } int main() { LL i , j , x , n , m ; char str[10] ; while(scanf("%I64d %I64d", &n, &m) !=EOF) { creat(root); while(m--) { scanf("%s", str); if(str[0] == 'C') { scanf("%I64d %I64d %I64d", &i, &j, &x); update(i,j,x,root); } else { scanf("%I64d %I64d", &i, &j); printf("%I64d\n", query(i,j,root,0)); } } } return 0; }