POJ 3468 A Simple Problem with Integers(区间更新+区间求和)

A Simple Problem with Integers
Time Limit: 5000MS   Memory Limit: 131072K
Total Submissions: 78622   Accepted: 24231
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

The sums may exceed the range of 32-bit integers.




ac代码:
#include<stdio.h>
struct s
{
	int left;
	int right;
	__int64 sum;
	__int64 lazy;
}tree[1000010];
__int64 num[100010];
void pushdown(int len,int i)
{
	if(tree[i].lazy)
	{
		tree[i*2].lazy+=tree[i].lazy;
		tree[i*2+1].lazy+=tree[i].lazy;
		tree[i*2].sum+=tree[i].lazy*(len-(len/2));
		tree[i*2+1].sum+=tree[i].lazy*(len/2);
		tree[i].lazy=0;
	}
}
void build(int l,int r,int i)
{
	tree[i].left=l;
	tree[i].right=r;
	tree[i].lazy=0;
	if(l==r)
	{
		tree[i].sum=num[l];
	}
	else
	{
		int mid=(l+r)/2;
		build(l,mid,i*2);
		build(mid+1,r,i*2+1);
		tree[i].sum=tree[i*2].sum+tree[i*2+1].sum;
    }
}
void update(int l,int r,__int64 c,int i)
{
	int mid=(tree[i].right+tree[i].left)/2;
	if(tree[i].left>=l&&tree[i].right<=r)
	{
		tree[i].lazy+=c;
		tree[i].sum+=c*(tree[i].right-tree[i].left+1);
		return;
	}
	pushdown(tree[i].right-tree[i].left+1,i);
    if(l<=mid)
    {
        update(l,r,c,i*2);
    }
    if(mid<r)
    {
        update(l,r,c,i*2+1);
    }
    tree[i].sum=tree[i*2].sum+tree[i*2+1].sum;
}
__int64 query(int l,int r,int i)
{
	int mid=(tree[i].left+tree[i].right)/2;
	__int64 ans=0;
	if(tree[i].left>=l&&tree[i].right<=r)
	{
		return tree[i].sum;
	}
	pushdown(tree[i].right-tree[i].left+1,i);
	if(l<=mid)
	{
		ans+=query(l,r,i*2);
	}
	if(r>mid)
	{
		ans+=query(l,r,i*2+1);
	}
	tree[i].sum=tree[i*2].sum+tree[i*2+1].sum;
	return ans;
}
int main()
{
	int i;
	int a,b,n,m;
	__int64 d;
	char ch[10];
	while(scanf("%d%d",&n,&m)!=EOF)
	{
		for(i=1;i<=n;i++)
		scanf("%I64d",&num[i]);
		build(1,n,1);
		for(i=0;i<m;i++)
		{
			scanf("%s",ch);
			if(ch[0]=='Q')
			{
				scanf("%d%d",&a,&b);
				printf("%I64d\n",query(a,b,1));
			}
			else
			{
				scanf("%d%d%I64d",&a,&b,&d);
				update(a,b,d,1);
			}
		}
	}
	return 0;
}


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