[HDOJ6154] CaoHaha's staff（规律, 打表, 二分）

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=6154

有些题一辈子只会做一次，比如这个题。。

题意：炒鸡难懂，学弟读明白的。懒得描述，反正这题以后不会再做。

f(i)表示i个线段能围成的最大面积，画画图就会发现一个规律。

然后查询的时候二分最小的大于等于s的即可。

  1 /*
  2 ━━━━━┒ギリギリ♂ eye！
  3 ┓┏┓┏┓┃キリキリ♂ mind！
  4 ┛┗┛┗┛┃＼○／
  5 ┓┏┓┏┓┃ /
  6 ┛┗┛┗┛┃ノ)
  7 ┓┏┓┏┓┃
  8 ┛┗┛┗┛┃
  9 ┓┏┓┏┓┃
 10 ┛┗┛┗┛┃
 11 ┓┏┓┏┓┃
 12 ┛┗┛┗┛┃
 13 ┓┏┓┏┓┃
 14 ┃┃┃┃┃┃
 15 ┻┻┻┻┻┻
 16 */
 17 #include <algorithm>
 18 #include <iostream>
 19 #include <iomanip>
 20 #include <cstring>
 21 #include <climits>
 22 #include <complex>
 23 #include <cassert>
 24 #include <cstdio>
 25 #include <bitset>
 26 #include <vector>
 27 #include <deque>
 28 #include <queue>
 29 #include <stack>
 30 #include <ctime>
 31 #include <set>
 32 #include <map>
 33 #include <cmath>
 34 using namespace std;
 35 #define fr first
 36 #define sc second
 37 #define cl clear
 38 #define BUG puts("here!!!")
 39 #define W(a) while(a--)
 40 #define pb(a) push_back(a)
 41 #define Rint(a) scanf("%d", &a)
 42 #define Rll(a) scanf("%lld", &a)
 43 #define Rs(a) scanf("%s", a)
 44 #define Cin(a) cin >> a
 45 #define FRead() freopen("in", "r", stdin)
 46 #define FWrite() freopen("out", "w", stdout)
 47 #define Rep(i, len) for(int i = 0; i < (len); i++)
 48 #define For(i, a, len) for(int i = (a); i < (len); i++)
 49 #define Cls(a) memset((a), 0, sizeof(a))
 50 #define Clr(a, x) memset((a), (x), sizeof(a))
 51 #define Full(a) memset((a), 0x7f7f7f, sizeof(a))
 52 #define lrt rt << 1
 53 #define rrt rt << 1 | 1
 54 #define pi 3.14159265359
 55 #define RT return
 56 #define lowbit(x) x & (-x)
 57 #define onenum(x) __builtin_popcount(x)
 58 typedef long long LL;
 59 typedef long double LD;
 60 typedef unsigned long long ULL;
 61 typedef pair<int, int> pii;
 62 typedef pair<string, int> psi;
 63 typedef pair<LL, LL> pll;
 64 typedef map<string, int> msi;
 65 typedef vector<int> vi;
 66 typedef vector<LL> vl;
 67 typedef vector<vl> vvl;
 68 typedef vector<bool> vb;
 69
 70 const int maxn = 1000100;
 71 const int inf = 0x7f7f7f7f;
 72 int s, n, R;
 73 int f[maxn];
 74
 75
 76 signed main() {
 77     // FRead();
 78     Cls(f);
 79     For(i, 1, maxn) {
 80         f[4*i] = i * i * 2;
 81         f[4*i+1] = 2 * i * i + i - 1;
 82         f[4*i+2] = i * i * 2 + 2 * i;
 83         f[4*i+3] = i * i * 2 + 3 * i;
 84         R = 4 * i + 4;
 85         if(f[4*i+3] > (int)1e9) break;
 86     }
 87     int T;
 88     Rint(T);
 89     W(T) {
 90         Rint(s);
 91         int lo = 3, hi = R;
 92         int ret;
 93         while(lo <= hi) {
 94             int mid = (lo + hi) >> 1;
 95             if(f[mid] >= s) {
 96                 ret = mid;
 97                 hi = mid - 1;
 98             }
 99             else lo = mid + 1;
100         }
101         printf("%d\n", ret);
102     }
103     RT 0;
104 }

[HDOJ6154] CaoHaha's staff（规律, 打表, 二分）