P1317 低洼地
模拟
1 #include<bits/stdc++.h> 2 using namespace std; 3 #define maxn 1000000 4 5 int n,h[maxn],tot; 6 bool if_; 7 char ch; 8 inline void read(int &now) 9 { 10 ch=getchar(); now=0; 11 while(ch>'9'||ch<'0') ch=getchar(); 12 while(ch>='0'&&ch<='9') now=now*10+ch-'0',ch=getchar(); 13 } 14 15 int main() 16 { 17 read(n); 18 for(int i=1;i<=n;i++) read(h[i]); 19 for(int i=1;i<=n;i++) 20 { 21 if(!if_&&h[i]<h[i-1]) if_=1; 22 if(if_&&h[i]>h[i-1]) if_=0,tot++; 23 } 24 printf("%d ",tot); 25 return 0; 26 }