有序选择L长度排列

http://acm.pku.edu.cn/JudgeOnline/problem?id=3049

 

参考别人代码写的：

 

#include<stdio.h>int L, C;char list[27], set[27];void find(int i, int vovel, int ith){if(ith == L){if(vovel)printf("%s/n", set);return ;}for(; i<=C-L+ith; i++){set[ith] = list[i];find(i+1, vovel+(set[ith] == 'a' || set[ith] == 'e' || set[ith] == 'i' || set[ith] == 'o' || set[ith] == 'u'), ith+1);}}int main(){int i, k, arr[123];char temp[2];while(scanf("%d%d", &L, &C) != EOF){for(i='a'; i<='z'; i++)arr[i] = 0;for(i=0; i<C; i++){scanf("%s", temp);arr[temp[0]] = 1;}for(i='a', k=0; i<='z'; i++)if(arr[i])list[k++] = i;set[L] = 0;find(0, 0, 0);}return 0;}