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　　bzoj2002 弹飞绵羊

这种写法不太好，容易错

 1 #include <iostream>
 2 #include <string.h>
 3 #include <cstdio>
 4 #include <queue>
 5 #include <vector>
 6 #include <cstring>
 7 #include <algorithm>
 8 #include <math.h>
 9 
10 #define SIGMA_SIZE 26
11 #pragma warning ( disable : 4996 )
12 
13 using namespace std;
14 typedef long long LL;
15 //typedef unsigned long long uLL;
16 
17 inline LL LMax(LL a,LL b)    { return a>b?a:b; }
18 inline LL LMin(LL a,LL b)    { return a>b?b:a; }
19 inline int Max(int a,int b) { return a>b?a:b; }
20 inline int Min(int a,int b) { return a>b?b:a; }
21 inline int gcd( int a, int b ) { return b==0?a:gcd(b,a%b); }
22 inline int lcm( int a, int b ) { return a/gcd(a,b)*b; }  //a*b = gcd*lcm
23 const long long INF = 0x3f3f3f3f3f3f3f3f;
24 const int inf  = 0x3f3f3f3f;
25 const int mod  = 7;
26 const int maxk = 5005;
27 const int maxn = 2e5+5;
28 
29 int n, m;
30 int ki[maxn];
31 int pos[maxn], times[maxn];
32 
33 int main()
34 {
35     cin >> n;
36     for ( int i = 0; i < n; i++ )
37         scanf("%d", &ki[i]);
38     cin >> m;
39 
40     int block = sqrt(n);
41 
42     for ( int i = n - 1; i >= 0; i-- )
43     {
44         int tmp = i+ki[i];
45         if ( tmp >= n )
46             { pos[i] = -1; times[i] = 1; }
47         else if ( tmp >= (i/block+1)*block )
48             { pos[i] = tmp; times[i] = 1; }
49         else
50             { pos[i] = pos[tmp]; times[i] = times[tmp]+1; }
51     }
52 
53     int x, y, k;
54     for ( int j = 0; j < m; j++ )
55     {
56         scanf("%d", &x);
57         if ( x == 2 )
58         {
59             scanf( "%d %d", &y, &k );
60             ki[y] = k;
61 
62             for ( int i = y; i >= (y / block)*block; i-- )
63             {
64                 int tmp = i+ki[i];
65                 if ( tmp >= n )
66                     { pos[i] = -1; times[i] = 1; }
67                 else if ( tmp >= (i/block+1)*block )
68                     { pos[i] = tmp; times[i] = 1; }
69                 else
70                     { pos[i] = pos[tmp]; times[i] = times[tmp] + 1; }
71             }
72         }
73         else
74         {
75             scanf("%d", &y);
76             int ans = 0;
77             for ( int i = y; i+1; i = pos[i] )
78                 ans += times[i]; 
79             printf( "%d\n", ans );
80         }
81     }
82 
83     return 0;
84 }
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posted @ 2018-04-20 19:46  LBNOQYX  阅读(118)  评论(0)  编辑  收藏  举报