标签：span mergesort col 数组下标 数组 逆序 sort 模板 ++
ps：数组下标从0开始哦！
①求逆序对版
int tmp[MAX],rec[MAX]; int sum;//求逆序对个数 void merge(int low,int mid,int high) { int i=low,j=mid+1,k=low; while(i<=mid&&j<=high) { if(rec[i]>rec[j]) { tmp[k++]=rec[j++]; sum+=mid-i+1; } else tmp[k++]=rec[i++]; } while(i<=mid) tmp[k++]=rec[i++]; while(j<=high) tmp[k++]=rec[j++]; for(i=low;i<=high;i++) rec[i]=tmp[i]; } void mergesort(int low,int high) { if(low<high) { int mid=(low+high)/2; mergesort(low,mid); mergesort(mid+1,high); merge(low,mid,high); } }
②纯归并排序（考研）
int tmp[MAX],rec[MAX]; void merge(int low,int mid,int high) { int i=low,j=mid+1,k=low; while(i<=mid&&j<=high) { if(rec[i]>rec[j]) tmp[k++]=rec[j++]; else tmp[k++]=rec[i++]; } while(i<=mid) tmp[k++]=rec[i++]; while(j<=high) tmp[k++]=rec[j++]; for(i=low;i<=high;i++) rec[i]=tmp[i]; } void mergesort(int low,int high) { if(low<high) { int mid=(low+high)/2; mergesort(low,mid); mergesort(mid+1,high); merge(low,mid,high); } }
标签：span mergesort col 数组下标 数组 逆序 sort 模板 ++
原文地址：https://www.cnblogs.com/kannyi/p/9381733.html
