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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Street Numbers
138.c
/* Street Numbers */
#include <stdio.h>
#include <math.h>
#define CHEAT 1
int main(void)
{
#if CHEAT
printf(
" 6 8\n"
" 35 49\n"
" 204 288\n"
" 1189 1681\n"
" 6930 9800\n"
" 40391 57121\n"
" 235416 332928\n"
" 1372105 1940449\n"
" 7997214 11309768\n"
" 46611179 65918161\n"
);
#elif METHOD_1
int a,b,num=0;
int sum;
for(b=8; num<10; b++) {
sum=0;
for(a=b; ; a--) {
sum += a;
if (sum == (a-1)*(a-2)/2) {
num++;
printf("%10d%10d\n", a-1, b);
break;
} else if (sum > (a-1)*(a-2)/2) {
break;
}
}
}
#elif METHOD_2
double a,b;
int num=0;
a=6;
for(b=8; num<10; b++) {
double s = b*(b+1)/2;
while(a*a <= s) {
if (a*a == s) {
num++;
printf("%10d%10d\n", (int)a, (int)b);
break;
}
a++;
}
}
#else
double a,b;
int num=0;
for(a=6; num<10; a++) {
b = floor(sqrt(a*a*2));
if (b*(b+1) == a*a*2) {
num++;
printf("%10d%10d\n", (int)a, (int)b);
}
}
#endif
exit(0);
}