A Simple Problem with Integers
| Time Limit: 5000MS | Memory Limit: 131072K | |
| Total Submissions: 55949 | Accepted: 16877 | |
| 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 51 2 3 4 5 6 7 8 9 10Q 4 4Q 1 10Q 2 4C 3 6 3Q 2 4
Sample Output
455915
wa了好多次，最后终于ac了
#include<stdio.h>
#include<algorithm>
using namespace std;
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
const int maxn=111111;
__int64 sum[maxn<<2]; //不定义__int64为必wa
__int64 vis[maxn<<2];
void pushup(int rt)
{
sum[rt]=sum[rt<<1]+sum[rt<<1|1];
}
void pushdown(int rt,int m)
{
if(vis[rt])
{
vis[rt<<1]+=vis[rt];
vis[rt<<1|1]+=vis[rt];
sum[rt<<1]+=(m-(m>>1))*vis[rt];
sum[rt<<1|1]+=(m>>1)*vis[rt];
vis[rt]=0; //这里最后记得置为零
}
}
void build(int l,int r,int rt)
{
vis[rt]=0;
if(l==r)
{
scanf("%I64d",&sum[rt]); //输入也要__int64
return;
}
int m=(l+r)>>1;
build(lson);
build(rson);
pushup(rt);
}
void update(int L,int R,int add,int l,int r,int rt)
{
if(L <=l&&R>=r)
{
vis[rt]+=add;
sum[rt]+=add*(r-l+1);
return;
}
pushdown(rt,r-l+1);
int m=(l+r)>>1;
if(L <=m)
update(L,R,add,lson);
if(R>m)
update(L,R,add,rson);
pushup(rt);
}
__int64 getsum(int L,int R,int l,int r,int rt)
{
__int64 ret=0; //因为这里没有定义__int64错了好几次
if(L <=l&&R >=r)
{
return sum[rt];
}
pushdown(rt,r-l+1); //求和也要pushdown？？反正我不明白为什么，以后再看
int m=(l+r)>>1;
if(L <=m)
ret+=getsum(L,R,lson);
if(R >m)
ret+=getsum(L,R,rson);
return ret;
}
int main()
{
int a,b,x,y,z,n,m;
char s[5];
scanf("%d%d",&n,&m);
build(1,n,1);
for(int i=0;i<m;i++)
{
scanf("%s",s);
if(s[0]=='Q')
{
scanf("%d%d",&a,&b);
printf("%I64d\n",getsum(a,b,1,n,1));
}
if(s[0]=='C')
{
scanf("%d%d%d",&x,&y,&z);
update(x,y,z,1,n,1);
}
}
return 0;
}