HDU 1166 敌兵布阵

树状数组：
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
int c[50024],sum[50024],N;
int lowbit(int x){
return x&(-x);
}
int SUM(int n){
int sum=0;
while(n){
sum=sum+c
;
n-=lowbit(n);
}
return sum;
}
void  add(int n,int num){
while(n<=N){
c
+=num;
n+=lowbit(n);
}
}
int main(){
int n;
scanf("%d",&n);
for(int i=1;i<=n;i++)
{char a[10];
int x,y,m;
sum[0]=0;c[0]=0;
scanf("%d",&N);
for(int j=1;j<=N;j++){
scanf("%d",&x);
sum[j]=sum[j-1]+x;
c[j]=sum[j]-sum[j-lowbit(j)];
}
printf("Case %d:\n",i);
while(scanf("%s",a),strcmp(a,"End")){
scanf("%d%d",&x,&y);
if(a[0]=='Q'){
int ans=SUM(y)-SUM(x-1);
printf("%d\n",ans);
}
else {
if(a[0]=='S')y=-y;
add(x,y);
}
}
//    puts("");
}
return 0;
}

线段数：
#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<string.h>
using namespace std;
class Node
{
public:
int l,r,mid;
int count;
};
Node tree[200024];
int num[50024];
class Tree
{
public:
void Maketree( int l,int r,int cnt );
void Add( int l,int r, int cnt);
int Qestion( int l,int r,int cnt );
};
void Tree::Maketree( int l,int r,int cnt )
{
if( l == r )
{
tree[cnt].l = tree[cnt].r = l;
tree[cnt].mid = l;
tree[cnt].count = num[l];
return ;
}
else
{
tree[cnt].l = l;
tree[cnt].r = r;
tree[cnt].mid = ( l + r )>>1;
Maketree( l , tree[cnt].mid , cnt*2 );
Maketree( tree[cnt].mid +1 , r, cnt*2 +1 );
tree[cnt].count = tree[cnt*2].count + tree[cnt*2+1].count;
}
}
void Tree::Add( int n,int m, int cnt )
{
if( tree[cnt].l == n&&tree[cnt].r==n )
{
tree[cnt].count += m;
return;
}
else
{
if( n > tree[cnt].mid )
Add( n , m , cnt*2+1 );
else Add( n , m ,cnt*2 );
tree[cnt].count += m;
}
}
int Tree::Qestion( int l,int r,int cnt )
{
if( l==tree[cnt].l&&r==tree[cnt].r )
return tree[cnt].count;
else
{
if( l > tree[cnt].mid )
return Qestion( l, r, cnt*2+1 );
else
{
if( r <= tree[cnt].mid )
return Qestion( l , r ,cnt*2 );
else
{
return Qestion( l , tree[cnt].mid, cnt*2 )+Qestion( tree[cnt].mid+1,r, cnt*2+1 );
}
}
}
}
int main( )
{
int Case,n,l,r;
char c[10];
while( scanf( "%d",&Case )==1 )
{
Tree e;
for( int i=1; i<=Case ; i++ )
{
printf( "Case %d:\n",i );
scanf( "%d",&n );
for( int j=1; j<= n; j++ )
scanf( "%d",&num[j] );
e.Maketree( 1,n,1 );
while( scanf( "%s",c ),c[0]!='E' )
{
scanf( "%d%d",&l,&r );
if( c[0]=='A' )
e.Add( l,r,1 );
else if( c[0]=='S' )
e.Add( l , -1*r,1 );
else printf( "%d\n",e.Qestion( l,r,1 ) );
}
}
}
return 0;
}