#include <bits/stdc++.h> using namespace std; const int inf=1e9; int n; vector <int> a[2]; inline int get_ans(bool b, int nr) { int ans=0; for(int i=1; i<n; ++i) { if(b && a[nr][i]<=a[nr][i-1]) { a[nr][i]=inf; ++ans; } else if((!b) && a[nr][i]>=a[nr][i-1]) { a[nr][i]=-inf; ++ans; } b=!b; } return ans; } int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); cin>>n; a[0].resize(n); a[1].resize(n); for(int i=0; i<n; ++i) { cin>>a[0][i]; a[1][i]=a[0][i]; } cout<<min(get_ans(0, 0), get_ans(1, 1))<<"\n"; return 0; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 | #include <bits/stdc++.h> using namespace std; const int inf=1e9; int n; vector <int> a[2]; inline int get_ans(bool b, int nr) { int ans=0; for(int i=1; i<n; ++i) { if(b && a[nr][i]<=a[nr][i-1]) { a[nr][i]=inf; ++ans; } else if((!b) && a[nr][i]>=a[nr][i-1]) { a[nr][i]=-inf; ++ans; } b=!b; } return ans; } int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); cin>>n; a[0].resize(n); a[1].resize(n); for(int i=0; i<n; ++i) { cin>>a[0][i]; a[1][i]=a[0][i]; } cout<<min(get_ans(0, 0), get_ans(1, 1))<<"\n"; return 0; } |