Submission #1559177


Source Code Expand

#include <bits/stdc++.h>
using namespace std;

#define rep(i,x,y) for(int i=(x);i<(y);++i)
#define debug(x) #x << "=" << (x)

#ifdef DEBUG
#define _GLIBCXX_DEBUG
#define print(x) std::cerr << debug(x) << " (L:" << __LINE__ << ")" << std::endl
#else
#define print(x)
#endif

const int inf=1e9;
const int64_t inf64=1e18;
const double eps=1e-9;

template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec){
    os << "[";
    for (const auto &v : vec) {
    	os << v << ",";
    }
    os << "]";
    return os;
}

using i64=int64_t;

void solve(){
    int N;
    cin >> N;
    vector<int> p(N);
    vector<bool> b(N);
    rep(i,0,N){
        cin >> p[i];
        --p[i];
        if(p[i]==i) b[i]=true;
    }

    int ans=0;
    rep(i,0,N){
        if(!b[i]) continue;
        ++ans;
        b[i]=false;
        if(i+1<N and b[i+1]) b[i+1]=false;
    }

    cout << ans << endl;
}

int main(){
    std::cin.tie(0);
    std::ios::sync_with_stdio(false);
    cout.setf(ios::fixed);
    cout.precision(16);
    solve();
    return 0;
}

Submission Info

Submission Time
Task D - Derangement
User walkre
Language C++14 (GCC 5.4.1)
Score 400
Code Size 1104 Byte
Status AC
Exec Time 10 ms
Memory 768 KB

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 400 / 400
Status
AC × 4
AC × 15
Set Name Test Cases
Sample 0_000.txt, 0_001.txt, 0_002.txt, 0_003.txt
All 0_000.txt, 0_001.txt, 0_002.txt, 0_003.txt, 1_004.txt, 1_005.txt, 1_006.txt, 1_007.txt, 1_008.txt, 1_009.txt, 1_010.txt, 1_011.txt, 1_012.txt, 1_013.txt, 1_014.txt
Case Name Status Exec Time Memory
0_000.txt AC 1 ms 256 KB
0_001.txt AC 1 ms 256 KB
0_002.txt AC 1 ms 256 KB
0_003.txt AC 1 ms 256 KB
1_004.txt AC 1 ms 256 KB
1_005.txt AC 9 ms 640 KB
1_006.txt AC 9 ms 640 KB
1_007.txt AC 9 ms 640 KB
1_008.txt AC 9 ms 640 KB
1_009.txt AC 9 ms 640 KB
1_010.txt AC 9 ms 640 KB
1_011.txt AC 9 ms 768 KB
1_012.txt AC 9 ms 640 KB
1_013.txt AC 10 ms 640 KB
1_014.txt AC 9 ms 640 KB