luogu P4275 萃香的请柬

嘟嘟嘟

打表不难发现,序列的长度以及序列中1的个数都是斐波那契数列。因为第 i 秒1的个数由 i - 1的1和 i - 2的0变换而来,那么f[i] = f[i - 1] + f[i - 2]。序列的长度同理,第 i 秒的序列长度由 i - 1秒的长度加上 i - 1 秒的1变换而来,而i - 1秒的1的个数就是 i - 2 秒的序列长度。

至此这道题已经做完了,但题解中有一个大佬还详细的证明,具体看这里

然后这题读了前面的字母会迷之GG,后面全RE,不读就AC.

 1 #include<cstdio>
 2 #include<iostream>
 3 #include<cmath>
 4 #include<algorithm>
 5 #include<cstring>
 6 #include<cstdlib>
 7 #include<cctype>
 8 #include<vector>
 9 #include<stack>
10 #include<queue>
11 using namespace std;
12 #define enter puts("") 
13 #define space putchar(' ')
14 #define Mem(a, x) memset(a, x, sizeof(a))
15 #define rg register
16 typedef long long ll;
17 typedef double db;
18 const int INF = 0x3f3f3f3f;
19 const db eps = 1e-8;
20 const int maxn = 93;
21 inline ll read()
22 {
23   ll ans = 0;
24   char ch = getchar(), last = ' ';
25   while(!isdigit(ch)) last = ch, ch = getchar();
26   while(isdigit(ch)) ans = (ans << 1) + (ans << 3) + ch - '0', ch = getchar();
27   if(last == '-') ans = -ans;
28   return ans;
29 }
30 inline void write(ll x)
31 {
32   if(x < 0) x = -x, putchar('-');
33   if(x >= 10) write(x / 10);
34   putchar(x % 10 + '0');
35 }
36 
37 ll f[maxn];
38 //char c[10];
39 
40 int main()
41 {
42   f[1] = f[2] = 1;
43   for(int i = 3; i < maxn; ++i) f[i] = f[i - 1] + f[i - 2];
44   //scanf("%s", c);  //??????????????????
45   ll q = read();
46   while(q--)
47     {
48       ll a = read(), b = read(); a--;
49       ll ans = 0;
50       for(int i = 91; i >= 0; --i)
51     {
52       if(a >= f[i] && b >= f[i]) a -= f[i], b -= f[i];
53       else if(a >= f[i]) a -= f[i], ans -= f[i - 1];
54       else if(b >= f[i]) b -= f[i], ans += f[i - 1];
55     }
56       write(ans), enter;
57     }
58   return 0;
59 }
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原文地址:https://www.cnblogs.com/mrclr/p/9875407.html