线段树/hdu1166 敌兵布阵

题意

　　n个阵营一字排开，每个初始有a[i]个人。现有两种操作：

　　Q a b 查询[a,b]之间总人数并输出

　　A/S a b 在a号位添加/删除b个人

分析

　　单点更新，区域查询的线段树模板

 

Accepted Code

pascal版，zsc写的

 1 Program hdu1166;

 2 Const

 3   Infile='hdu1166.in';

 4   Outfile='hdu1166.out';

 5 Type

 6   jl=Record

 7     l,r,w:Longint;

 8   End;

 9 Var

10   tree:Array[0..200000] Of jl;

11   a:Array[0..50000] OF Longint;

12   ch,ch1:Char;

13   n,z,t,i,x,y:Longint;

14 Procedure Build(x,l,r:Longint);

15 Var

16   mid:Longint;

17 Begin

18   tree[x].l:=l;tree[x].r:=r;

19   If (l=r) Then Begin

20     tree[x].w:=a[l];

21     Exit;

22   End;

23   mid:=(l+r) Div 2;

24   If l<=mid Then Build(2*x,l,mid);

25   If mid <r Then Build(2*x+1,mid+1,r);

26   tree[x].w:=tree[2*x].w+tree[2*x+1].w;

27 End;

28 Function Query(x,l,r:Longint):Longint;

29 Var

30   anslchild,ansrchild,mid:Longint;

31 Begin

32   If (l<=tree[x].l)And(tree[x].r<=r) Then Begin

33     Query:=tree[x].w;

34     Exit;

35   End;

36   mid:=(tree[x].l+tree[x].r) Div 2;

37   anslchild:=0;

38   ansrchild:=0;

39   If l<=mid Then anslchild:=Query(2*x,l,r);

40   If mid <r Then ansrchild:=Query(2*x+1,l,r);

41   Query:=anslchild+ansrchild;

42 End;

43 Procedure Add(x,pos,w:Longint);

44 Var

45   mid:Longint;

46 Begin

47   If (tree[x].l=tree[x].r) Then Begin

48     tree[x].w:=tree[x].w+w;

49     Exit;

50   End;

51   mid:=(tree[x].l+tree[x].r) Div 2;

52   If pos<=mid Then Add(2*x,pos,w) Else Add(2*x+1,pos,w);

53   tree[x].w:=tree[2*x].w+tree[2*x+1].w;

54 End;

55 Begin

56   Assign(Input,Infile);

57   Assign(Output,Outfile);

58   Reset(Input);

59   Rewrite(Output);

60   Readln(t);

61   For z:=1 To t Do Begin

62     Writeln('Case ',z,':');

63     Fillchar(tree,Sizeof(tree),0);

64     Readln(n);

65     For i:=1 To n Do Read(a[i]);

66     Build(1,1,n);

67     Readln;

68     Read(ch);

69     While (ch<>'E') Do Begin

70       Read(ch1);

71       While (ch1<>' ') Do Read(Ch1);

72       Readln(x,y);

73       If (Ch='Q') Then Writeln(Query(1,x,y));

74       If (ch='A') Then Add(1,x,y);

75       If (ch='S') Then Add(1,x,-1*y);

76       Read(ch);

77     End;

78     Readln;

79   End;

80   Close(Input);

81   Close(Output);

82 End.

c++版 

 1 /*

 2      PROBLEM:hdu1166

 3      AUTHER:Rinyo

 4      MEMO:线段树

 5 */

 6 

 7 #include<cstdio>

 8 #include<cstring>

 9 using namespace std;

10 const int maxn(50030);

11 int ans;

12 struct node

13 {

14     int left,right,sum;

15 

16 }tree[4*maxn];

17 void maketree(int left,int right,int x)

18 {

19     tree[x].left=left;tree[x].right=right;

20     if (left==right) 

21     {

22         scanf("%d",&tree[x].sum);

23         return;

24     }

25     int mid=(left+right)>>1;

26     maketree(left,mid,x<<1);

27     maketree(mid+1,right,x<<1|1);

28     tree[x].sum=tree[x<<1].sum+tree[x<<1|1].sum;

29 }

30 void query(int left,int right,int x,int l,int r)

31 {

32     if (l<=left && right<=r)

33     {

34         ans+=tree[x].sum;

35         return;

36     }

37     int mid=(left+right)>>1;

38     if (r<=mid) query(left,mid,x<<1,l,r);

39     else if (l>mid) query(mid+1,right,x<<1|1,l,r);

40     else 

41     {

42         query(left,mid,x<<1,l,r);

43         query(mid+1,right,x<<1|1,l,r);

44     }

45 }

46 void update(int left,int right,int x,int pos,int add)

47 {

48     if (left==right)

49     {

50         tree[x].sum+=add;

51         return;

52     }

53     int mid=(left+right)>>1;

54     if (pos<=mid) update(left,mid,x<<1,pos,add);

55     else update(mid+1,right,x<<1|1,pos,add);

56     tree[x].sum=tree[x<<1].sum+tree[x<<1|1].sum;

57 }

58 int main()

59 {

60     freopen("1166.txt","r",stdin);

61     int t,n,cnt,a,b;

62     char str[10];

63     cnt=1;

64     scanf("%d",&t);

65     while (t--)

66     {

67         scanf("%d",&n);

68         maketree(1,n,1);

69         printf("Case %d:\n",cnt++);

70         while (scanf("%s",str))

71         {

72             if (str[0]=='E') break;

73             scanf("%d%d",&a,&b);

74             if (str[0]=='Q') 

75             {

76                 ans=0;

77                 query(1,n,1,a,b);

78                 printf("%d\n",ans);

79             }

80             else if (str[0]=='A') update(1,n,1,a,b);

81             else update(1,n,1,a,-b);

82         }

83     }

84     return 0;

85 }