【剑指Offer学习】【面试题28 ：字符串的排列】

https://blog.youkuaiyun.com/qq_25024883/article/details/79657992

 

void doEnumList(char a[], int len, int start) {
    if (start == len-1) {
        NSString *string_content = [[NSString alloc] initWithCString:(const char*)a
                                                            encoding:NSASCIIStringEncoding];
        NSLog(@"%@\r\n",string_content);
    }
    char temp;
    for (int i=start; i<len; i++) {
        temp = a[i];
        a[i] = a[start];
        a[start] = temp;
        doEnumList(a,len,start+1);
        // 递归完需要还原位置
        a[start] = a[i];
        a[i] = temp;
    }
}
    
bool enumList(char a[], int len) {
    if(a == NULL || 0 == len) {
        return false;
    }
    doEnumList(a,len,0);
    return true;
}


    char aList[] = {'a','b','c','d','e'};
    enumList(aList,5);