sort和qsort对字符数组排序
#include <iostream>#include <cstdlib>#include <cstring>#include <algorithm>using namespace std;//升序比较:第一个元素比第二个元素大返回正数（这是元素需要交换的条件）int compare_rise(const void *a,const void *b) { return *(char*)a - *(char*)b;}//降序比较:第二个元素比第一个元素大返回正数（这是元素需要交换的条件）int compare_fail(const void *a,const void *b) { return *(char*)b - *(char*)a ;}int cmp_sort(char a, char b) { return a > b;}void display( const char *array1, int len ) { for(int i = 0; i< len; ++i) { cout << array1[i] << " "; } cout << endl;}void qsort_char() { char str[] = "XELMNFUVWGYRSTZAHIJKBOPQCD"; int len = strlen( str ); cout << "原始数据:" << endl; display( str, len ); cout << "升序排序后:" << endl; qsort(str, len, sizeof (*str), compare_rise); ///不必包含#include <algorithm> display( str, len ); cout << "降序排序后:" << endl; qsort(str, len, sizeof (*str), compare_fail); display( str, len );}void sort_char() { char ch[100] = "XELMNFUVWGYRSTZAHIJKBOPQCD\n"; int len = strlen(ch); //cout << "please input a string: " ; // cin >> ch; ///scanf("%s", ch);or gets(ch); cout << "升序排序后: "; sort(ch, ch+strlen(ch)); //必须包含#include <algorithm> display(ch, len); cout << "降序排序后: " << endl; sort(ch, ch+strlen(ch), cmp_sort); display(ch, len);}int main() { qsort_char(); sort_char(); return 0;}