Shuffle-12174 Method

Question: Question Link

Idea: see zishu. I still don't understand the specific operation method. The code is from a question. I will review it later and need to understand it.

Code:

1 # include <iostream> 2 # include <cstring> 3 # include <set> 4 using namespace STD; 5 6 const int n = 1e5 + 5; 7 8 int S, N, A [n], vis [N]; 9 bool flag [N]; 10 int ans; 11 12 Void Init () 13 {14 CIN> S> N; 15 int num = 0; 16 for (INT I = 0; I <n; I ++) 17 {18 CIN> A [I]; 19 if (I <s) 20 {// analyze the previous s. 21 if (vis [A [I]) 22 num ++; // count the repeated number 23 vis [A [I] ++; 24} 25} 26 27 for (INT I = 0; I <N; I ++) 28 {29/ /If num = 0, it indicates that there are no repeated numbers in the first S, then the first number can be used as the start of the loop 30 if (num = 0) 31 flag [I] = true; 32 33 // The window starts to slide 34 if (vis [A [I] = 2) 35 num --; // if at this time the leftmost number is repeated, num needs to be reduced by 136 vis [A [I] --; 37 38 int K = I + S; // new number enters the Sliding Window 39 if (k> = N) 40 continue; 41 if (vis [A [k]) 42 num ++; // If 43 vis [A [k] ++ already exists; 44} 45} 46 47 bool judge (int x) 48 {49 for (INT I = x; I <n; I + = s) 50 if (! Flag [I]) 51 return false; 52 return true; 53} 54 55 void solve () 56 {57 memset (VIS, 0, sizeof (VIS )); 58 59 ans = 0; 60 for (INT I = 0; I <s; I ++) 61 {62 if (Judge (I) 63 ans ++; 64 if (I> = N) 65 continue; 66 // traverse from left to right. If a [I] already exists before it, it must start, in this case, the loop 67 If (vis [A [I]) 68 break; 69 vis [A [I] ++; 70} 71} 72 73 int main () 74 {75 // freopen ("D: \ txt.txt", "r", stdin); 76 int t; 77 CIN> T; 78 while (t --) 79 {80 memset (flag, 0, sizeof (FLAG); 81 memset (VIS, 0, sizeof (VIS); 82 Init (); 83 solve (); 84 cout <ans <Endl; 85} 86 return 0; 87}

 

Shuffle-12174 Method