标签:排序 NPU lld script 题解 序列 接下来 col span
1 #include <cstdio> 2 #include <iostream> 3 #include <cstring> 4 using namespace std; 5 const long long inf=1000000000; 6 long long n,a[100010],mx,l,sum[100010]; 7 long long ans; 8 long long getsum(long long x) 9 { 10 long long num=0; 11 while (x>0) 12 { 13 num+=sum[x]; 14 x-=x&-x; 15 } 16 return num; 17 } 18 void update(long long x) 19 { 20 while (x<=n) 21 { 22 sum[x]++; 23 x+=x&-x; 24 } 25 } 26 void swap(long long l,long long r) 27 { 28 long long b[100010]; 29 for (long long i=l;i<=r;i++) b[i]=a[r-i+l]; 30 for (long long i=l;i<=r;i++) a[i]=b[i]; 31 } 32 int main() 33 { 34 scanf("%lld",&n); 35 for (long long i=1;i<=n;i++) scanf("%lld",&a[i]); 36 mx=inf; l=1; 37 for (long long i=1;i<=n;i++) 38 { 39 if (mx<a[i]) 40 { 41 if (l!=i-1) 42 { 43 ans++; 44 swap(l,i-1); 45 mx=a[i]; l=i; 46 } 47 } 48 else mx=a[i]; 49 } 50 if (l<n) swap(l,n),ans++; 51 for (long long i=n;i>=1;i--) 52 { 53 ans+=getsum(a[i]); 54 update(a[i]); 55 } 56 printf("%lld",ans); 57 return 0; 58 }
标签:排序 NPU lld script 题解 序列 接下来 col span
原文地址:https://www.cnblogs.com/Comfortable/p/9337924.html