线段树（区间修改+区间查询）

qwq ， ylx 问我要一份线段树的版 ， 可我线段树一直是10分钟 ，从不写版 ，qwq ，还是放一份版在这 。

题目见：http://poj.org/problem?id=3468

  1 #include <iostream>
  2 #include <cstring>
  3 #include <cstdlib>
  4 #include <cstdio>
  5 const int inf = 1<<30 , maxn = 100000 + 11 ;
  6 using namespace std;
  7 int n , q , cnt ;
  8 struct id
  9 {
 10      long long  sum , lazy ;
 11 }tree[maxn<<2] ;
 12
 13 long long int read(  ) {
 14     char ch = getchar(  ) ; long long int ret = 0 , k = 1 ;
 15     while( ch < ‘0‘ || ch > ‘9‘ ) { if( ch == ‘-‘ ) k = -1 ; ch = getchar(  ) ; }
 16     while( ch >= ‘0‘ && ch <= ‘9‘ ) ret = ret * 10 + ch - ‘0‘ , ch = getchar(  ) ;
 17     return ret * k ;
 18 }
 19
 20
 21
 22 void set_lazy( int num , int l , int r )
 23 {
 24     int m = r - l + 1 ;
 25     if( tree[num].lazy )
 26     {
 27         tree[num<<1].lazy += tree[num].lazy ;
 28         tree[(num<<1)+1].lazy += tree[num].lazy ;
 29         tree[num<<1].sum += tree[num].lazy * ( m - (m>>1) ) ;
 30         tree[(num<<1)+1].sum += tree[num].lazy * ( m>>1 ) ;
 31         tree[num].lazy = 0ll ;
 32     }
 33
 34 }
 35
 36 void update( int l , int r , int num , int L , int R , int add )
 37 {
 38     if( l == L && r == R )
 39     {
 40         tree[num].sum += 1ll*add * ( R - L + 1 ) ;
 41         tree[num].lazy += add ;
 42         return ;
 43     }
 44     if( l == r ) return ;
 45     set_lazy( num , l , r ) ;
 46     int mid = l + ( ( r - l ) >> 1 );
 47     if( R <= mid ) update( l , mid , num<<1 , L , R , add ) ;
 48     else if( L > mid ) update( mid+1 , r , (num<<1)+1 , L , R , add ) ;
 49     else
 50     {
 51         update( l , mid , num<<1 , L , mid , add ) ;
 52         update( mid+1 , r , (num<<1)+1 , mid+1 , R , add ) ;
 53     }
 54     tree[num].sum = tree[num<<1].sum + tree[(num<<1)+1].sum ;
 55 }
 56
 57
 58 long long int quer( int l , int r , int num , int L , int R )
 59 {
 60     if( l == L && R == r ) return tree[num].sum ;
 61     set_lazy( num , l , r ) ;
 62     int mid = l + ( ( r - l ) >> 1 ) ;
 63     if( R <= mid ) return quer( l , mid , num<<1 , L , R ) ;
 64     else if( L > mid ) return quer( mid + 1 , r , (num<<1)+1 , L , R ) ;
 65     else return quer( l  , mid  , num<<1 , L , mid ) + quer( mid+1 , r , (num<<1)+1 , mid+1 , R ) ;
 66 }
 67
 68
 69 void build( int num , int l , int r )
 70 {
 71     tree[num].lazy = 0ll ;
 72     if( l == r )
 73     {
 74         tree[num].sum = read( ) ;
 75         return ;
 76     }
 77     int mid = l + ( ( r - l ) >> 1 ) ;
 78
 79     build( num<<1 , l , mid ) ;
 80     build( (num<<1)+1 , mid+1 , r ) ;
 81     tree[num].sum = tree[num<<1].sum + tree[(num<<1)+1].sum ;
 82 }
 83
 84 int main( )
 85 {
 86     n = read( ) , q = read( ) ;
 87     build( 1 , 1 , n  ) ;
 88     for( int  x = 1 ; x <= q ; ++x )
 89     {
 90         char a ; int b , c , d ;
 91         scanf( "%s" , &a ) ;
 92         b = read( ) , c = read( ) ;
 93         if( a == ‘C‘ )
 94         {
 95             d = read( ) ;
 96             update( 1 , n , 1 , b , c , d ) ;
 97         }
 98         if( a == ‘Q‘ )
 99         {
100             printf( "%lld\n" , quer( 1 , n , 1 , b , c ) ) ;
101         }
102     }
103 }