HDU 1166 敌兵布阵

题目连接：http://acm.hdu.edu.cn/showproblem.php?pid=1166

#include<cstdio>
#include<cstdlib>
#include<cmath>
#include<cstring>
#define MAXN 50005
int seg_tree[MAXN<<2];
void build_tree(int l,int r,int id);
int query_tree(int left,int right,int l,int r,int id);
void update_point_tree(int left,int right,int value,int l,int r,int id);
void push_up_tree(int id);
int main()
{
int tcase,n,i,left,right,value;
char str[20];
while(scanf("%d",&tcase)==1)
{
for(i=1;i<=tcase;i++)
{
printf("Case %d:\n",i);
scanf("%d",&n);
build_tree(1,n,1);
while(scanf("%s",str)!=EOF)
{
if(!strcmp(str,"Query"))
{
scanf("%d%d",&left,&right);
printf("%d\n",query_tree(left,right,1,n,1));
}
if(!strcmp(str,"Add"))
{
scanf("%d%d",&left,&value);
update_point_tree(left,left,value,1,n,1);

}
if(!strcmp(str,"Sub"))
{
scanf("%d%d",&left,&value);
update_point_tree(left,left,-value,1,n,1);
}
if(!strcmp(str,"End"))
break;
}

}

}
}
void build_tree(int l,int r,int id)
{
if(l==r)
{
scanf("%d",&seg_tree[id]);
return ;
}
int mid=(l+r)/2;
build_tree(l,mid,id<<1);
build_tree(mid+1,r,id<<1|1);
push_up_tree(id);

}
int query_tree(int left,int right,int l,int r,int id)
{
if(left<=l&&right>=r)
return seg_tree[id];
int mid=(l+r)>>1,ret=0;
if(left<=mid)
ret+=query_tree(left,right,l,mid,id<<1);
if(right>mid)
ret+=query_tree(left,right,mid+1,r,id<<1|1);
return ret;
}
void update_point_tree(int left,int right,int value,int l,int r,int id)
{
if(l==r)
{ seg_tree[id]+=value;
return ;}
int mid=(l+r)>>1;
if(left<=mid)
update_point_tree(left,right,value,l,mid,id<<1);
else
update_point_tree(left,right,value,mid+1,r,id<<1|1);
push_up_tree(id);

}
void push_up_tree(int id)
{
seg_tree[id]=seg_tree[id<<1]+seg_tree[id<<1|1];
}