diff options
Diffstat (limited to 'palindrome.c')
-rw-r--r-- | palindrome.c | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/palindrome.c b/palindrome.c new file mode 100644 index 0000000..aad741a --- /dev/null +++ b/palindrome.c @@ -0,0 +1,59 @@ +#include <stdlib.h> +#include <stdio.h> +#include <string.h> + +int isPalindrome(long num){ + long len = 0; + long n = num; + while(n != 0){ + n = n / 10; + len++; + } + char *numchar = (char *) malloc (len * sizeof(char)); + sprintf(numchar, "%ld", num); + //printf("%s\n", numchar); + // Backwards counter + long j = len - 1; + // Forwards counter + long i = 0; + + while(i < len){ + if(numchar[i] != numchar[j]) + return 0; + i++; + j--; + } + return 1; +} + +long *findProduct(long num){ + for(long i = 999; i > 100; i--) + for(long j = 999; j > 100; j--) + if(i * j == num){ + long *facts = (long *) malloc (2 * sizeof(long)); + facts[0] = i; + facts[1] = j; + return facts; + } +} + +long findMaxPalindrome(){ + long large = 0; + for(long i = 999; i > 100; i--){ + for(long j = 999; j > 100; j--){ + long test = i * j; + if(isPalindrome(test) && test > large){ + large = test; + } + } + } + return large; +} + +int main(){ + long answer = findMaxPalindrome(); + printf("%d\n", answer); + long *prod = findProduct(answer); + printf("The factors are %d and %d\n", prod[0], prod[1]); +} + |