Photolog
2010-10-12: Through the Looking-Glass
2010-10-10: My radio speaks is binary!
2010-09-16: Gigaminx: (present for my birthday)
2010-09-05: Trini on bike
2010-08-28: Valporquero
2010-08-22: My new bike!
2010-08-13: Mario and Ana's wedding
2010-08-07: Canyoning in Guara
2010-08-05: Trini and Mari in Marbella
2010-08-03: Trini and Chelo in Tabarca
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The 3n + 1 problem
100.c
/* Trivial */
#include <stdio.h>
int algorithm(int n)
{
int length=1;
while(n!=1) {
if (n%2) {
n = 3*n+1;
} else {
n = n/2;
}
length++;
}
return length;
}
#define MIN(a,b) ((a) < (b) ? (a) : (b))
#define MAX(a,b) ((a) > (b) ? (a) : (b))
int main()
{
int i,j;
while(scanf("%d %d", &i, &j)==2) {
int n;
int maximum=0;
for(n=MIN(i,j); n<=MAX(i,j); n++) {
int a = algorithm(n);
maximum = (maximum>a) ? maximum : a;
}
printf("%d %d %d\n", i, j, maximum);
}
exit(0);
}