一个字符数组，里面的字符可能是a-z、A-Z、0-9.现在要求对数组进行排序，要求所有小写字符放在最前面，所有大写字符放在中间，所有数字放在最后，而且各部分内部分别有序（创新工场）

一个字符数组，里面的字符可能是a-z、A-Z、0-9.现在要求对数组进行排序，要求所有小写字符放在最前面，所有大写字符放在中间，所有数字放在最后，而且各部分内部分别有序。思路：先进行字符串排序，用堆排序，按降序排列，排列依据字母对应的ascii值。排序之后按字符类别进行翻转。时间复杂度O（nlogn）

#include<string>#include<iostream>using namespace std;void swap(char* a, char* b) {char temp = *a;*a= *b;*b = temp;}void heapAdjust(char* str, int i, int length) {int lchild = 2 * i + 1;int rchild = 2 * i + 2;int minIndex;if (lchild < length && str[lchild] < str[i])minIndex = lchild;elseminIndex = i;if (rchild < length && str[rchild] < str[minIndex])minIndex = rchild;if (minIndex != i) {swap(str + i, str + minIndex);heapAdjust(str, minIndex, length);}}void heapSort(char* str, int length) {int i;for (i = length / 2; i >= 0; i--)heapAdjust(str, i, length);for (i = length - 1; i > 0; i--) {swap(str + i, str + 0);heapAdjust(str, 0, i);}}void revserStr(char* pStart, char* pEnd) {char charTemp;while (pStart < pEnd) {charTemp = *pStart;*pStart = *pEnd;*pEnd = charTemp;pStart++;pEnd--;}}void rearrangeStr(char* pStr, int length) {heapSort(pStr, length);int i, startIndex = 0, endIndex = -1;for (i = 0; i < length; i++) {if (pStr[i] >= 'a' && pStr[i] <= 'z') {endIndex++;} else {break;}}if (endIndex > startIndex)revserStr(pStr + startIndex, pStr + endIndex);startIndex = endIndex + 1;for (; i < length; i++) {if (pStr[i] >= 'A' && pStr[i] <= 'Z') {endIndex++;} else {break;}}if (endIndex > startIndex)revserStr(pStr + startIndex, pStr + endIndex);startIndex = endIndex + 1;for (; i < length; i++) {if (pStr[i] >= '0' && pStr[i] <= '9') {endIndex++;} else {break;}}if (endIndex > startIndex)revserStr(pStr + startIndex, pStr + endIndex);}int main(int argc, char* argv[]) {char str[] = "MDEXE098FGH453a4cf9";int length = strlen(str);rearrangeStr(str, length);cout << str << endl;cin.get();return 0;}