Arrange the array into the smallest number.

68. Arrange the array into the smallest number.
Question: enter an array of Positive Integers to join them into a number and output the smallest of all the numbers that can be discharged.
For example, if the input array is {32,321}, the minimum numbers 32132 that can be arranged are output.
Provide an algorithm to solve the problem and prove the algorithm.
Analysis: this is an interview question from Baidu in September June,
From this question, we can see that Baidu has a high requirement on algorithms.

 

 

[Cpp]
/*
Name:
Copyright:
Author:
Date: 25-06-11 :19
Description: The minimum number of arrays (arrays and algorithms ).
Question: enter an array of Positive Integers to join them into a number and output all the numbers that can be discharged.
The smallest one.
For example, if the input array is {32,321}, the minimum numbers 32132 that can be arranged are output.
Provide an algorithm to solve the problem and prove the algorithm.
*/
# Include <iostream>
# Include <iomanip>
Using namespace std;
# Define N 10 // There are N integers in total
Bool cmp_min (char * s1, char * s2)
// Algorithm guarantee, s1 and s2 are not empty strings
{
Const int slen1 = strlen (s1 );
Const int slen2 = strlen (s2 );
Char * tc = (char *) malloc (slen1 + slen2 + 1); // only open up one space
Int I;
For (I = 0; I <slen2; ++ I)
Tc [I] = s2 [I];
For (; I <slen1 + slen2; ++ I)
Tc [I] = s1 [i-slen2];
Tc [I] = '\ 0 ';
For (I = 0; I <slen1; ++ I)
{
If (s1 [I] = tc [I])
Continue;
Else
{
If (s1 [I]> tc [I])
Return false;
Else
Return true;
}
}
For (; I <slen1 + slen2; ++ I)
{
If (s2 [i-slen1] = tc [I])
Continue;
Else
{
If (s1 [i-slen1]> tc [I])
Return false;
Else
Return true;
}
}
Return false;
}
 
Int sort_partition (char * s [], int p, int r)
{
Char * x = s [r];
Int I = p-1;
Int j;
Char * tem;
For (j = p; j <r; ++ j)
{
If (cmp_min (s [j], x ))
{
Tem = s [++ I];
S [I] = s [j];
S [j] = tem;
}
}
Tem = s [++ I];
S [I] = x;
S [r] = tem;
Return I;
}
 
Void quick_sort (char * s [], int p, int r)
{
Int m;
If (p <r)
{
M = sort_partition (s, p, r );
Quick_sort (s, p m-1 );
Quick_sort (s, m + 1, r );
}

}
Int main ()
{
// Z has N integers in total
Int a [N] = {67,234,901 };
Char * s [N]; // pointer Array
For (int I = 0; I <N; ++ I)
{// Convert to N strings
S [I] = (char *) malloc (sizeof (char) * 12 );
// An integer expressed by 11
Itoa (a [I], s [I], 10 );
// Contains '\ 0'
}
For (int I = 0; I <N; I ++)
{
Cout <s [I] <"";
}
Quick_sort (s, 0, 9 );
Cout <endl;
For (int I = 0; I <N; I ++)
{
Cout <s [I] <"";
}
System ("pause ");
Return 0;
}

/*
Name:
Copyright:
Author:
Date: 25-06-11 :19
Description: The minimum number of arrays (arrays and algorithms ).
Question: enter an array of Positive Integers to join them into a number and output all the numbers that can be discharged.
The smallest one.
For example, if the input array is {32,321}, the minimum numbers 32132 that can be arranged are output.
Provide an algorithm to solve the problem and prove the algorithm.
*/
# Include <iostream>
# Include <iomanip>
Using namespace std;
# Define N 10 // There are N integers in total
Bool cmp_min (char * s1, char * s2)
// Algorithm guarantee, s1 and s2 are not empty strings
{
Const int slen1 = strlen (s1 );
Const int slen2 = strlen (s2 );
Char * tc = (char *) malloc (slen1 + slen2 + 1); // only open up one space
Int I;
For (I = 0; I <slen2; ++ I)
Tc [I] = s2 [I];
For (; I <slen1 + slen2; ++ I)
Tc [I] = s1 [i-slen2];
Tc [I] = '\ 0 ';
For (I = 0; I <slen1; ++ I)
{
If (s1 [I] = tc [I])
Continue;
Else
{
If (s1 [I]> tc [I])
Return false;
Else
Return true;
}
}
For (; I <slen1 + slen2; ++ I)
{
If (s2 [i-slen1] = tc [I])
Continue;
Else
{
If (s1 [i-slen1]> tc [I])
Return false;
Else
Return true;
}
}
Return false;
}

Int sort_partition (char * s [], int p, int r)
{
Char * x = s [r];
Int I = p-1;
Int j;
Char * tem;
For (j = p; j <r; ++ j)
{
If (cmp_min (s [j], x ))
{
Tem = s [++ I];
S [I] = s [j];
S [j] = tem;
}
}
Tem = s [++ I];
S [I] = x;
S [r] = tem;
Return I;
}

Void quick_sort (char * s [], int p, int r)
{
Int m;
If (p <r)
{
M = sort_partition (s, p, r );
Quick_sort (s, p m-1 );
Quick_sort (s, m + 1, r );
}

}
Int main ()
{
// Z has N integers in total
Int a [N] = {67,234,901 };
Char * s [N]; // pointer Array
For (int I = 0; I <N; ++ I)
{// Convert to N strings
S [I] = (char *) malloc (sizeof (char) * 12 );
// An integer expressed by 11
Itoa (a [I], s [I], 10 );
// Contains '\ 0'
}
For (int I = 0; I <N; I ++)
{
Cout <s [I] <"";
}
Quick_sort (s, 0, 9 );
Cout <endl;
For (int I = 0; I <N; I ++)
{
Cout <s [I] <"";
}
System ("pause ");
Return 0;
}
It is a fast sorting, and the comparison operation adopts the symbol overload method. This question is still quite interesting.