线段树加深poj3468ASimpleProblemwithIntegers

#include 
#include 
#include <string.h>

using namespace std;
struct cnode{
             int x,y;
             cnode *left,*right;
             long long sum,ans;   //设置ans结点 保存C 操作每个区间加上的值赋给ans
            }tree[220000];           //是输入数据的2n-1个  开辟静态的存储空间

int count=0;
long long sum=0;
void buildtree(cnode *proot,int s,int e)     //建树
{
    proot->x=s;
    proot->y=e;
    proot->sum=proot->ans=0;
    if(s==e)return;
    else {
           count++;
           proot->left=tree+count;
           count++;
           proot->right=tree+count;
           buildtree(proot->left,s,(s+e)/2);
           buildtree(proot->right,(s+e)/2+1,e);
         }
}

void insert(cnode *proot,int i,long long num)   //插入数据
{
    if(proot->x==i&&proot->y==i){proot->sum+=num;return ;}
    else{
         proot->sum+=num;
         if(i<=(proot->x+proot->y)/2) insert(proot->left,i,num);
         else insert(proot->right,i,num);
        }
}

void jia(cnode *proot,int s,int e,long long num)        //作用一添加区间上的值 作用二 在query函数中调用此函数将ans的值往下传
{
         if(proot->x==s&&proot->y==e ){proot->ans+=num;return ;}
               proot->sum+=(e-s+1)*num;                   //更新包含这个区间的值
               if( e<=(proot->x+proot->y)/2 )jia(proot->left,s,e,num);
               else {

                     if(s>=(proot->x+proot->y)/2+1) jia(proot->right,s,e,num);
                     else {
                              jia(proot->left,s,(proot->x+proot->y)/2,num);
                              jia(proot->right,(proot->x+proot->y)/2+1,e,num);
                          }
                       }
}

void query(cnode *proot,int s,int e)
{
  if(proot->x==s&&proot->y==e){sum+=proot->sum+(e-s+1)*proot->ans;return;}
  else{
            {
                           proot->sum+=(proot->y-proot->x+1)*proot->ans;              //这个是容易出错的地方  先改变sum值,再传值,再将ans置0;
                           jia(proot->left,proot->x,(proot->x+proot->y)/2,proot->ans);
                           jia(proot->right,(proot->x+proot->y)/2+1,proot->y,proot->ans);
                           proot->ans=0;
                         }
                 if( e<=(proot->x+proot->y)/2 )query(proot->left,s,e);
               else {
                     if(s>=(proot->x+proot->y)/2+1) query(proot->right,s,e);
                     else {
                             query(proot->left,s,(proot->x+proot->y)/2);
                             query(proot->right,(proot->x+proot->y)/2+1,e);
                          }
                    }
      }
}

int main()
{
    int n,m,i,s,e;
    long long num;
    char judge[3];
    while(scanf("%d %d",&n,&m)!=EOF)
    {

     count=0;
      buildtree(tree,1,n);
     for( i=1;i<=n;i++)
      {
      scanf("%I64d",&num);
      insert(tree,i,num);
      }
     for(i=1;i<=m;i++)
     {
       scanf("%s",judge);
       if(judge[0]=='Q'){scanf("%d %d",&s,&e);sum=0;query(tree,s,e);printf("%I64d\n",sum);}
       if(judge[0]=='C'){scanf("%d %d %I64d",&s,&e,&num);jia(tree,s,e,num);}
     }

    }
}