Run Length Encoding of String

/*
You have a character array containing upper and lower case letters of the English alphabet. Do a run-length encoding of the array.
e.g. if the array is aaaBBAcc, its run-length encoding is a3B2Ac2.
Function prototype is

char * runLengthEncode(char * A)

Note: Make sure you take care of critical cases like when the count of a character exceeds 9

*/


#include
#include
#include
#define MAX_RLEN 50

/* Returns the Run Length Encoded string for the
source string src */
char *encode(char *src)
{
int rLen;
char count[MAX_RLEN];
int len = strlen(src);
int p=0;

/* If all characters in the source string are different,
then size of destination string would be twice of input string.
For example if the src is "abcd", then dest would be "a1b1c1"
For other inputs, size would be less than twice. */
char *dest = (char *)malloc(sizeof(char)*(len*2 + 1));

int i, j = 0, k;

/* traverse the input string one by one */
for(i = 0; i < len; i++)
{

/* Copy the first occurrence of the new character */
dest[j++] = src[i];

/* Count the number of occurrences of the new character */
rLen = 1;
while(i + 1 < len && src[i] == src[i+1])
{
rLen++;
i++;
}

/* Store rLen in a character array count[] */
sprintf(count, "%d", rLen);//it will resolve problem when count>9

//count[p]=((char)rLen);//it will create problem when count>9
p++;

/* Copy the count[] to destination */
for(k = 0; *(count+k); k++, j++)
{
dest[j] = count[k];
}
}

/*terminate the destination string */
dest[j] = '\0';
return dest;
}

/*driver program to test above function */
int main()
{
char str[] = "aaaaaaaaaaaaaaabbbbbcd";
char *res = encode(str);
printf("%s", res);
getchar();
}