C. Omkar and Baseball
解题思路
附上代码
#pragma GCC optimize("-Ofast","-funroll-all-loops")
#include<bits/stdc++.h>
#define int long long
#define lowbit(x) (x &(-x))
#define endl '\n'
using namespace std;
const int INF=0x3f3f3f3f;
const int dir[4][2]={-1,0,1,0,0,-1,0,1};
const double PI=acos(-1.0);
const double e=exp(1.0);
const double eps=1e-10;
const int M=1e9+7;
const int N=2e5+10;
typedef long long ll;
typedef pair<int,int> PII;
typedef unsigned long long ull;
inline void read(int &x){
char t=getchar();
while(!isdigit(t)) t=getchar();
for(x=t^48,t=getchar();isdigit(t);t=getchar()) x=x*10+(t^48);
}
int a[N];
signed main(){
ios::sync_with_stdio(false);
cin.tie(0);cout.tie(0);
int t;
cin>>t;
while(t--){
int n;
cin>>n;
int ass=0;
for(int i=1;i<=n;i++){
cin>>a[i];
if(a[i-1]!=i-1&&a[i]==i)
ass++;
}
if(a[n]!=n) ass++;
if(ass==0)
cout<<0<<endl;
else{
if(ass==1) cout<<1<<endl;
else cout<<2<<endl;
}
}
return 0;
}