void partitionOddandEvenHelper(int N, int * partition, int pos)
{
//BASE CASE
if(N == 0)
{
printPartition(partition, pos);
return;
}
//INDUCTIVE CASE
int i;
for(i = 1; i <= N; i++)
{
int val = 0;
if(pos == 0)
{
val = 1;
}
else
{
val = (partition[pos - 1] % 2) != (i % 2);
}
if(val == 1)
{
partition[pos] = i;
partitionOddandEvenHelper(N - i, partition, pos + 1);
}
}
}
void partitionOddAndEven(int value)
{
printf("partitionOddAndEven %d\n", value);
int n=value;
if (n <= 0)
{
return;
}
int * arr;
arr = malloc(sizeof(int) * n);
partitionOddandEvenHelper(arr, 0, n);
free (arr);
return;
}
/*
* =================================================================
* This function prints alternate ood and even number partitions of a positive integer value. Each partition starts from and odd number, even number, ood number again, even number again...etc.
*
* For example, if value is 6
* 1 + 2 + 1 + 2 and
* 3 + 2 + 1 are valid partitions
*
* 6 is not a valid partition
*
* 2 + 1 + 1 + 2 and
* 2 + 1 + 3and
* 5 + 1 are invalid partitions.
*
* The program should generate only valid partitions. Do not
* generates invalid partitions and checks validity before printing.
*/
void partitionOddandEvenHelper(int * part, int ind, int left)
{
int val;
if (left == 0)
{
printPartition(part, ind);
return;
}
for (val = 1; val <= left; val ++)
{
if((val%2 ==1 && ind%2==0) || ((val%2==0 && ind%2==1)))
{
part[ind] = val;
partitionOddandEvenHelper(part, ind + 1, left - val);
}
}
}
void partitionOddAndEven(int value)
{
int *partition = malloc(sizeof(int) * value);
partitionOddandEvenHelper(value, partition, 0);
free(partition);
}
