最大下标距离（算法）

给定一个整形数组，找出最大下标距离j - i，当且仅当 a[i] <a[j] 和 j >ｉ

int maxIndexDistance(int a[]){if(a == null || a.length < 2) return 0;boolean inDescSeq[] = new boolean[a.length];int min = a[0],n = a.length;inDescSeq[0] = true;for(int i = 0; i < n; i++){if(a[i] < min){inDescSeq[i] = true;min = a[i];}}int maxDist = 0,i = n -1,j = n -1;while(i > = 0){if(inDescSeq[i ] == false){i--;continue;}while(a[j] < a[i] && j > i){j --;}if((j - i) > maxDist && j > i){maxDist = j - i;}i --;}return maxDist;}