Submission #890805
Source Code Expand
#include "bits/stdc++.h" #include "ext/pb_ds/tree_policy.hpp" #include "ext/pb_ds/assoc_container.hpp" #define PB push_back #define PF push_front #define LB lower_bound #define UB upper_bound #define fr(x) freopen(x,"r",stdin) #define fw(x) freopen(x,"w",stdout) #define in(x) (read(x)) #define iout(x) printf("%d\n",x) #define lout(x) printf("%lld\n",x) #define REP(x,l,u) for(ll x = l;x<u;x++) #define RREP(x,l,u) for(ll x = l;x>=u;x--) #define complete_unique(a) a.erase(unique(a.begin(),a.end()),a.end()) #define mst(x,a) memset(x,a,sizeof(x)) #define all(a) a.begin(),a.end() #define PII pair<int,int> #define PLL pair<ll,ll> #define MP make_pair #define sqr(x) ((x)*(x)) #define lowbit(x) (x&(-x)) #define lson (ind<<1) #define rson (ind<<1|1) #define se second #define fi first #define dbg(x) cout<<#x<<" = "<<(x)<<endl; #define sz(x) ((int)x.size()) typedef long long ll; typedef unsigned long long ull; typedef double db; typedef long double ld; using namespace std; const int block_size = 320; typedef complex<ll> point; const ll mod = 1e9+7; const ld eps = 1e-9; const int inf = mod; const db PI = atan(1)*4; template<typename T> inline int sign(const T&a){if(a<0)return -1;if(a>0)return 1;return 0;} template<typename T> inline void in(T &x){ x = 0; T f = 1; char ch = getchar(); while (!isdigit(ch)) {if (ch == '-') f = -1; ch = getchar();} while (isdigit(ch)) {x = x * 10 + ch - '0'; ch = getchar();} x *= f; } const int maxn = 100010; int f[maxn]; int main(){ int n;cin>>n; REP(i,1,n+1)cin>>f[i]; int ans = 0; REP(i,1,n+1)if(f[f[i]]==i)ans++; ans/=2; cout<<ans; return 0; }
Submission Info
Submission Time | |
---|---|
Task | B - Friendly Rabbits |
User | samzhang |
Language | C++14 (GCC 5.4.1) |
Score | 200 |
Code Size | 1676 Byte |
Status | AC |
Exec Time | 35 ms |
Memory | 640 KB |
Judge Result
Set Name | Sample | All | ||||
---|---|---|---|---|---|---|
Score / Max Score | 0 / 0 | 200 / 200 | ||||
Status |
|
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Set Name | Test Cases |
---|---|
Sample | 0_00.txt, 0_01.txt, 0_02.txt |
All | 0_00.txt, 0_01.txt, 0_02.txt, 1_00.txt, 1_01.txt, 1_02.txt, 1_03.txt, 1_04.txt, 1_05.txt, 1_06.txt, 1_07.txt, 1_08.txt, 1_09.txt, 1_10.txt, 1_11.txt |
Case Name | Status | Exec Time | Memory |
---|---|---|---|
0_00.txt | AC | 2 ms | 256 KB |
0_01.txt | AC | 2 ms | 256 KB |
0_02.txt | AC | 2 ms | 256 KB |
1_00.txt | AC | 2 ms | 256 KB |
1_01.txt | AC | 34 ms | 640 KB |
1_02.txt | AC | 35 ms | 640 KB |
1_03.txt | AC | 35 ms | 640 KB |
1_04.txt | AC | 34 ms | 640 KB |
1_05.txt | AC | 35 ms | 640 KB |
1_06.txt | AC | 34 ms | 640 KB |
1_07.txt | AC | 34 ms | 640 KB |
1_08.txt | AC | 14 ms | 384 KB |
1_09.txt | AC | 29 ms | 512 KB |
1_10.txt | AC | 25 ms | 512 KB |
1_11.txt | AC | 8 ms | 256 KB |