Submission #104225

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
104225	2019-04-04T10:28:19 Z	RockyB	The Big Prize (IOI17_prize)	C++17	100 / 100	77 ms	5500 KB

prize

#include "prize.h"
#include "bits/stdc++.h"
using namespace std;
bool done[200001];
vector < int > mem[200001];
vector < int > myask(int idx){
	if(done[idx]){
		return mem[idx];
	}
	done[idx] = 1;
	return mem[idx] = ask(idx);
}
int solve(int rsmall , int ql , int qr , int mx){
	if(ql > qr){
		return -1;
	}
	int l = ql;
	int r = qr;
	while(l < r){
		int mid = l + r >> 1;
		vector < int > tmp = myask(mid);
		if(tmp[0] + tmp[1] == 0){
			return mid;
		}
		if(tmp[0] + tmp[1] == mx){
			if(rsmall - tmp[1]){
				r = mid - 1;
			}
			else{
				l = mid + 1;
			}
		}
		else{
			r = mid;
		}
	}
	while(l <= qr){
		vector < int > tmp = myask(l);
		if(tmp[0] + tmp[1] == 0){
			return l;
		}
		if(tmp[0] + tmp[1] == mx){
			break;
		}
		++l;
	}
	if(l == qr + 1){
		return -1;
	}
	if(mem[l][1] - mem[qr + 1][1]){
		return solve(myask(l)[1] , l + 1 , qr , mx);
	}
	return -1;
}
int find_best(int n){
	int mx = 0;
	memset(done , 0 , sizeof(done));
	int groups = 460;
	int small = n / 460;
	int large = small + 1;
	int cur = 0;
	vector < int > ids;
	ids.clear();
	for(int i = 0 ; i < groups ; ++i){
		vector < int > res = myask(cur);
		mx = max(mx , res[0] + res[1]);
		if(res[0] + res[1] == 0){
			return cur;
		}
		ids.push_back(cur);
		if(i < (n % 460)){
			cur += large;
		}
		else{
			cur += small;
		}
	}
	done[n] = 1;
	mem[n] = {mx , 0};
	ids.push_back(n);
	for(int i = 0 ; i + 1 < ids.size() ; ++i){
		int x = ids[i];
		int y = ids[i + 1];
		int res = -1;
		if(mem[x][0] + mem[x][1] == mx && mem[y][0] + mem[y][1] == mx){
			if(mem[x][1] - mem[y][1]){
				res = solve(mem[x][1] , x + 1 , y - 1 , mx);
			}
			else{
				res = -1;
			}
		}
		else if(mem[x][0] + mem[x][1] == mx && mem[y][0] + mem[y][1] < mx){
			while(y >= x){
				vector < int > tmp = myask(y);
				if(tmp[0] + tmp[1] == 0){
					return y;
				}
				if(tmp[0] + tmp[1] == mx){
					break;
				}
				--y;
			}
			if(y == x - 1){
				res = -1;
			}
			else{
				if(mem[x][1] - mem[y][1]){
					res = solve(mem[x][1] , x + 1 , y - 1 , mx);
				}
				else{
					res = -1;
				}			
			}
		}
		else{
			while(x <= y){
				vector < int > tmp = myask(x);
				if(tmp[0] + tmp[1] == 0){
					return x;
				}
				if(tmp[0] + tmp[1] == mx){
					break;
				}
				++x;
			}
			if(x == y + 1){
				res = -1;	
			}
			else{
				if(mem[y][0] + mem[y][1] == mx){
					if(mem[x][1] - mem[y][1]){
						res = solve(mem[x][1] , x + 1 , y - 1 , mx);
					}
					else{
						res = -1;
					}
				}
				else{
					while(y >= x){
						vector < int > tmp = myask(y);
						if(tmp[0] + tmp[1] == 0){
							return y;
						}
						if(tmp[0] + tmp[1] == mx){
							break;
						}
						--y;
					}
					if(y == x - 1){
						res = -1;
					}
					else{
						if(mem[x][1] - mem[y][1]){
							res = solve(mem[x][1] , x + 1 , y - 1 , mx);
						}
						else{
							res = -1;
						}			
					}
				}
			}
		}
		if(res != -1){
			return res;
		}
	}
}

Compilation message

prize.cpp: In function 'int solve(int, int, int, int)':
prize.cpp:20:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   int mid = l + r >> 1;
             ~~^~~
prize.cpp: In function 'int find_best(int)':
prize.cpp:81:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0 ; i + 1 < ids.size() ; ++i){
                  ~~~~~~^~~~~~~~~~~~
prize.cpp:168:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

Subtask #1

20.0 / 20.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	9 ms	5332 KB	Output is correct
2	Correct	9 ms	5332 KB	Output is correct
3	Correct	12 ms	5112 KB	Output is correct
4	Correct	11 ms	5220 KB	Output is correct
5	Correct	10 ms	5248 KB	Output is correct
6	Correct	7 ms	5248 KB	Output is correct
7	Correct	10 ms	5324 KB	Output is correct
8	Correct	15 ms	5160 KB	Output is correct
9	Correct	11 ms	5240 KB	Output is correct
10	Correct	13 ms	5248 KB	Output is correct

Subtask #2

80.0 / 80.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	5112 KB	Output is correct
2	Correct	8 ms	5324 KB	Output is correct
3	Correct	11 ms	5112 KB	Output is correct
4	Correct	12 ms	5120 KB	Output is correct
5	Correct	9 ms	5324 KB	Output is correct
6	Correct	6 ms	5248 KB	Output is correct
7	Correct	8 ms	5324 KB	Output is correct
8	Correct	10 ms	5324 KB	Output is correct
9	Correct	11 ms	5112 KB	Output is correct
10	Correct	12 ms	5120 KB	Output is correct
11	Correct	12 ms	5112 KB	Output is correct
12	Correct	13 ms	5112 KB	Output is correct
13	Correct	15 ms	5240 KB	Output is correct
14	Correct	13 ms	5120 KB	Output is correct
15	Correct	13 ms	5336 KB	Output is correct
16	Correct	45 ms	5240 KB	Output is correct
17	Correct	13 ms	5240 KB	Output is correct
18	Correct	42 ms	5240 KB	Output is correct
19	Correct	12 ms	5248 KB	Output is correct
20	Correct	23 ms	5256 KB	Output is correct
21	Correct	14 ms	5360 KB	Output is correct
22	Correct	10 ms	5332 KB	Output is correct
23	Correct	8 ms	5324 KB	Output is correct
24	Correct	12 ms	5240 KB	Output is correct
25	Correct	24 ms	5336 KB	Output is correct
26	Correct	23 ms	5212 KB	Output is correct
27	Correct	8 ms	5220 KB	Output is correct
28	Correct	23 ms	5340 KB	Output is correct
29	Correct	19 ms	5412 KB	Output is correct
30	Correct	14 ms	5116 KB	Output is correct
31	Correct	11 ms	5160 KB	Output is correct
32	Correct	10 ms	5228 KB	Output is correct
33	Correct	7 ms	5120 KB	Output is correct
34	Correct	26 ms	5140 KB	Output is correct
35	Correct	8 ms	5324 KB	Output is correct
36	Correct	12 ms	5316 KB	Output is correct
37	Correct	10 ms	5332 KB	Output is correct
38	Correct	12 ms	5240 KB	Output is correct
39	Correct	26 ms	5244 KB	Output is correct
40	Correct	42 ms	5344 KB	Output is correct
41	Correct	27 ms	5240 KB	Output is correct
42	Correct	31 ms	5240 KB	Output is correct
43	Correct	32 ms	5244 KB	Output is correct
44	Correct	28 ms	5336 KB	Output is correct
45	Correct	24 ms	5240 KB	Output is correct
46	Correct	12 ms	5112 KB	Output is correct
47	Correct	24 ms	5212 KB	Output is correct
48	Correct	42 ms	5240 KB	Output is correct
49	Correct	15 ms	5112 KB	Output is correct
50	Correct	43 ms	5404 KB	Output is correct
51	Correct	23 ms	5240 KB	Output is correct
52	Correct	15 ms	5160 KB	Output is correct
53	Correct	12 ms	5132 KB	Output is correct
54	Correct	28 ms	5240 KB	Output is correct
55	Correct	13 ms	5160 KB	Output is correct
56	Correct	37 ms	5428 KB	Output is correct
57	Correct	36 ms	5240 KB	Output is correct
58	Correct	21 ms	5392 KB	Output is correct
59	Correct	30 ms	5288 KB	Output is correct
60	Correct	29 ms	5248 KB	Output is correct
61	Correct	11 ms	5304 KB	Output is correct
62	Correct	13 ms	5244 KB	Output is correct
63	Correct	13 ms	5248 KB	Output is correct
64	Correct	11 ms	5240 KB	Output is correct
65	Correct	9 ms	5300 KB	Output is correct
66	Correct	15 ms	5168 KB	Output is correct
67	Correct	11 ms	5240 KB	Output is correct
68	Correct	16 ms	5240 KB	Output is correct
69	Correct	11 ms	5224 KB	Output is correct
70	Correct	10 ms	5112 KB	Output is correct
71	Correct	46 ms	5240 KB	Output is correct
72	Correct	11 ms	5260 KB	Output is correct
73	Correct	46 ms	5304 KB	Output is correct
74	Correct	33 ms	5400 KB	Output is correct
75	Correct	12 ms	5120 KB	Output is correct
76	Correct	77 ms	5328 KB	Output is correct
77	Correct	27 ms	5440 KB	Output is correct
78	Correct	17 ms	5120 KB	Output is correct
79	Correct	21 ms	5168 KB	Output is correct
80	Correct	47 ms	5288 KB	Output is correct
81	Correct	26 ms	5444 KB	Output is correct
82	Correct	44 ms	5368 KB	Output is correct
83	Correct	12 ms	5248 KB	Output is correct
84	Correct	23 ms	5500 KB	Output is correct
85	Correct	43 ms	5240 KB	Output is correct
86	Correct	12 ms	5168 KB	Output is correct
87	Correct	10 ms	5320 KB	Output is correct
88	Correct	16 ms	5248 KB	Output is correct
89	Correct	19 ms	5240 KB	Output is correct
90	Correct	11 ms	5120 KB	Output is correct
91	Correct	18 ms	5240 KB	Output is correct
92	Correct	12 ms	5320 KB	Output is correct
93	Correct	25 ms	5240 KB	Output is correct
94	Correct	22 ms	5240 KB	Output is correct
95	Correct	24 ms	5240 KB	Output is correct
96	Correct	16 ms	5240 KB	Output is correct
97	Correct	17 ms	5240 KB	Output is correct