hdu 1698+poj 3468 (线段树 区间更新)

http://acm.hdu.edu.cn/showproblem.php?pid=1698

这个题意翻译起来有点猥琐啊,还是和谐一点吧

和涂颜色差不多,区间初始都为1,然后操作都是将x到y改为z,注意 是改为z,不是加或减,最后输出区间总值

也是线段树加lazy操作

 1 #include<cstdio>
 2 using namespace std;
 3 struct point {
 4     int l,r;
 5     int val,sum;
 6 };
 7 point tree[400007];
 8 void build(int i,int left,int right)
 9 {
10     tree[i].l=left,tree[i].r=right;
11     tree[i].val=0;
12     if (left==right) {tree[i].sum=1;return;}
13     int mid=(left+right)/2;
14     build(i*2,left,mid);
15     build(i*2+1,mid+1,right);
16     tree[i].sum=tree[i*2].sum+tree[i*2+1].sum;
17 }
18 int update(int i,int left,int right,int val)
19 {
20     if (right==tree[i].r&&left==tree[i].l)
21     {
22         tree[i].val=val;
23         return tree[i].sum=(right-left+1)*val;
24     }
25     if (tree[i].val)
26     {
27         tree[i*2].val=tree[i*2+1].val=tree[i].val;
28         tree[i*2].sum=(tree[i*2].r-tree[i*2].l+1)*tree[i].val;
29         tree[i*2+1].sum=(tree[i*2+1].r-tree[i*2+1].l+1)*tree[i].val;
30         tree[i].val=0;
31     }
32     int mid=(tree[i].r+tree[i].l)/2;
33     if (left>mid) return tree[i].sum=update(i*2+1,left,right,val)+tree[i*2].sum;
34     else if (right<=mid) return tree[i].sum=update(i*2,left,right,val)+tree[i*2+1].sum;
35     else  return tree[i].sum=update(i*2+1,mid+1,right,val)+update(i*2,left,mid,val);
36 }
37 int main()
38 {
39     int t,n,m,x,y,z,sum;
40     while (~scanf("%d",&t))
41     {
42         sum=1;
43         while (t--)
44         {
45             scanf("%d %d",&n,&m);
46             build(1,1,n);
47             while (m--)
48             {
49                 scanf("%d %d %d",&x,&y,&z);
50                 update(1,x,y,z);
51             }
52             printf("Case %d: The total value of the hook is %d.\n",sum++,tree[1].sum);
53         }
54     }
55     return 0;
56 }

http://poj.org/problem?id=3468

这个和上面一样,只是变成了加上z,所以就变成了在原有的值上再加,+=，改改就行,数值比较大,应该用int64

 1 #include<cstdio>
 2 #define ll __int64
 3 using namespace std;
 4 struct point {
 5     ll l,r;
 6     ll val,sum;
 7 };
 8 point tree[400007];
 9 ll num[100007];
10 void build(ll i,ll left,ll right)
11 {
12     tree[i].l=left,tree[i].r=right;
13     tree[i].val=0;
14     if (left==right) {tree[i].sum=num[left];return;}
15     int mid=(left+right)/2;
16     build(i*2,left,mid);
17     build(i*2+1,mid+1,right);
18     tree[i].sum=tree[i*2].sum+tree[i*2+1].sum;
19 }
20 ll update(ll i,ll left,ll right,ll val)
21 {
22     if (right==tree[i].r&&left==tree[i].l)
23     {
24         tree[i].val+=val;
25         return tree[i].sum+=(right-left+1)*val;
26     }
27     if (tree[i].val)
28     {
29         tree[i*2].val+=tree[i].val;
30         tree[i*2+1].val+=tree[i].val;
31         tree[i*2].sum+=(tree[i*2].r-tree[i*2].l+1)*tree[i].val;
32         tree[i*2+1].sum+=(tree[i*2+1].r-tree[i*2+1].l+1)*tree[i].val;
33         tree[i].val=0;
34     }
35     int mid=(tree[i].r+tree[i].l)/2;
36     if (left>mid) return tree[i].sum=update(i*2+1,left,right,val)+tree[i*2].sum;
37     else if (right<=mid) return tree[i].sum=update(i*2,left,right,val)+tree[i*2+1].sum;
38     else  return tree[i].sum=update(i*2+1,mid+1,right,val)+update(i*2,left,mid,val);
39 }
40 ll find(ll i,ll left,ll right)
41 {
42     if (left>tree[i].r&&right<tree[i].l) return 0;
43     if (tree[i].l==left&&tree[i].r==right) return tree[i].sum;
44     if (tree[i].val)
45     {
46         tree[i*2].val+=tree[i].val;
47         tree[i*2+1].val+=tree[i].val;
48         tree[i*2].sum+=(tree[i*2].r-tree[i*2].l+1)*tree[i].val;
49         tree[i*2+1].sum+=(tree[i*2+1].r-tree[i*2+1].l+1)*tree[i].val;
50         tree[i].val=0;
51     }
52     ll mid=(tree[i].r+tree[i].l)/2;
53     if (left>mid) return find(i*2+1,left,right);
54     else if (right<=mid) return find(i*2,left,right);
55     else return find(i*2,left,mid)+find(i*2+1,mid+1,right);
56 }
57 int main()
58 {
59     ll n,m,i,z,x,y;
60     char op;
61     while (~scanf("%I64d %I64d",&n,&m))
62     {
63        for (i=1;i<=n;i++)
64           scanf("%I64d",&num[i]);
65        build(1,1,n);
66        while (m--)
67        {
68            scanf(" %c",&op);
69            if (op==‘C‘)
70            {
71                scanf("%I64d %I64d %I64d",&x,&y,&z);
72                update(1,x,y,z);
73            }
74            else
75            {
76                scanf("%I64d %I64d",&x,&y);
77                printf("%I64d\n",find(1,x,y));
78            }
79        }
80     }
81     return 0;
82 }