Description
It is 2084 and the year of Big Brother has finally arrived, albeit a century late. In order to exercise greater control over its citizens and thereby to counter a chronic breakdown in law and order, the Government decides on a radical measure--all citizens are to have a tiny microcomputer surgically implanted in their left wrists. This computer will contains all sorts of personal information as well as a transmitter which will allow people's movements to be logged and monitored by a central computer. (A desirable side effect of this process is that it will shorten the dole queue for plastic surgeons.)
An essential component of each computer will be a unique identification code, consisting of up to 50 characters drawn from the 26 lower case letters. The set of characters for any given code is chosen somewhat haphazardly. The complicated way in which the code is imprinted into the chip makes it much easier for the manufacturer to produce codes which are rearrangements of other codes than to produce new codes with a different selection of letters. Thus, once a set of letters has been chosen all possible codes derivable from it are used before changing the set.
For example, suppose it is decided that a code will contain exactly 3 occurrences of `a', 2 of `b' and 1 of `c', then three of the allowable 60 codes under these conditions are:
abaabc
abaacb
ababac
These three codes are listed from top to bottom in alphabetic order. Among all codes generated with this set of characters, these codes appear consecutively in this order.
Write a program to assist in the issuing of these identification codes. Your program will accept a sequence of no more than 50 lower case letters (which may contain repeated characters) and print the successor code if one exists or the message `No Successor' if the given code is the last in the sequence for that set of characters.
Input and Output
Input will consist of a series of lines each containing a string representing a code. The entire file will be terminated by a line consisting of a single#.
Output will consist of one line for each code read containing the successor code or the words `No Successor'.
Sample input
abaacb cbbaa #
Sample output
ababac No Successor題目大意：（題外話）George Orwell在《1984》中談及的老大哥在2084年來到。政府在每個公民體內植入電腦芯片監視控制公民的一舉一動，電腦芯片同時具備發射信號的功能。爲了確定電腦ID號碼，政府給出了一套規則：每個ID號由3個'a'兩個'b'一個'c'構成。給定若干ID codes，求它們的下一個字典序全排列。
思路1：先求出當前排列要變化的子串的首字母下標，若不存在該字母，即已經完成了全排列，則輸出No Successor，否則繼續算法。再將首字母前一個字母同子串中從後到前第一個字典序大於前者的字母進行交換，之後對子串排序，得出目標（target）數組(array)，算法結束。
思路1：
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
char str[101];
bool cmp(const char x,const char y)
{return x<y;}
int main()
{
while(scanf("%s",str)&&str[0]!='#'){
int k;
for(k=strlen(str)-1;k>=1;k--)
if(str[k]>str[k-1])
break;
if(!k){puts("No Successor");continue;}
for(int i=strlen(str)-1;i>=k;i--)
if(str[i]>str[k-1])
{swap(str[i],str[k-1]);break;}
sort(str+k,str+strlen(str),cmp);
puts(str);
}
return 0;
}
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
char str[101];
int main()
{
while(scanf("%s",str)&&str[0]!='#'){
if(next_permutation(str,str+strlen(str)))
puts(str);
else puts("No Successor");
memset(str,0,sizeof(str));
}
return 0;
}