Kmin of Array
【本文链接】
http://www.cnblogs.com/hellogiser/p/kmin-of-array.html
【代码】
C++ Code
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/*
version: 1.0 author: hellogiser blog: http://www.cnblogs.com/hellogiser date: 2014/5/30 */ int Partition(int a[], int left, int right) { // partition so that a[left..p-1]<=a[p] and a[p+1..right]>a[p] int pivot = a[left], i = left , j = right; while (i < j) { while (a[i] <= pivot) i++; while (a[j] > pivot) j--; if (i < j) myswap(a[i], a[j]); } myswap(a[left], a[j]); return j; } int Kmin(int a[], int left, int right, int k) { // a[left..right], 1<=k<=n if(left <= right) // less or equal { int p = Partition(a, left, right); int pk = p - left + 1; if( k < pk) return Kmin(a, left, p - 1, k); // left searc else if(k > pk ) return Kmin(a, p + 1, right, k - pk); // right search else return a[p]; } return NOT_FOUND; } int Kmin(int a[], int n, int k) { if (k < 1 || k > n) return NOT_FOUND; return Kmin(a, 0, n - 1, k); } |
【本文链接】