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-rw-r--r--inf/liga/2.c118
1 files changed, 118 insertions, 0 deletions
diff --git a/inf/liga/2.c b/inf/liga/2.c
new file mode 100644
index 0000000..25ccbe5
--- /dev/null
+++ b/inf/liga/2.c
@@ -0,0 +1,118 @@
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <unistd.h>
+#include <string.h>
+#define M 512
+#define pedantic_fgets(a, b, c) if (!fgets(a, b, c)) { fprintf(stderr, "napaka pri vnosu\n"); return 1; }
+struct p {
+ long long int a;
+ long long int b;
+};
+int main (void) {
+ char buf[M];
+ char * cp;
+ long long int m, n, s, a, b, c;
+ m = n = s = a = b = c = 0; /* uh */
+ pedantic_fgets(buf, M, stdin);
+ m = strtoll(buf, &cp, 10);
+ if (!*++cp) return 1;
+ n = strtoll(cp, NULL, 10);
+ struct p * r = calloc(M, sizeof(struct p));
+ int u = 0;
+ fprintf(stderr, "interval je [%lld; %lld]\n", m, n);
+#if 0
+ for (a = 1; a <= n; a++)
+ for (b = 1; b <= n; b++)
+ for (c = 1; c <= n; c++) {
+ if (c >= m && c <= n && a*a+b*b == c*c) {
+ for (int i = 0; i < u; i++) {
+ if ((r[i].a == a && r[i].b == b)
+ || (r[i].a == b && r[i].b == a)) {
+#ifndef EVAL
+ fprintf(stderr, "ogabno\n");
+#endif
+ goto ogabno;
+ }
+ }
+ r[u].a = a;
+ r[u++].b = b;
+#ifndef EVAL
+ fprintf(stderr, "%lld² + %lld² = %lld²\n", a, b, c);
+#endif
+ s++;
+ogabno:;
+ }
+ }
+ fprintf(stdout, "%lld\n", s);
+#endif
+#if 0
+ for (int a = 1; a <= n; a++)
+ for (int b = a+1; b <= n; b++) { /* a < b, b < c <= pravzaprav to sploh ni res*/
+ for (c = b+1; c*c < a*a+b*b; c++); /* koren je počasnejši */
+ if (c >= m && c <= n && a*a + b*b == c*c)
+ s++;
+ }
+#endif
+#if 0 /* eulerjeva metoda ne generira vseh trojic */
+ /* a = x² - y²
+ b = 2xy
+ c = x²+y² */
+#define COND (c < 100)
+ for (int x = 2; COND; x++) {
+ for (int y = 1; y < x; y++) {
+ c = x*x+y*y;
+#ifndef EVAL
+ a = x*x-y*y;
+ b = 2*x*y;
+ fprintf(stderr, "%d²+%d²=%d² ", a, b, c);
+#endif
+ if (c >= m && c <= n) {
+#ifndef EVAL
+ fprintf(stderr, "ŠTEJEMO\n");
+#endif
+ s++;
+ }
+#ifndef EVAL
+ else {
+ fprintf(stderr, "NE ŠTEJEMO\n");
+ }
+#endif
+ }
+ }
+#endif
+#if 0
+ for (a = 1; a <= n; a++)
+ for (b = 1; b <= n; b++) {
+ double e = a*a+b*b;
+ double d = sqrt(e);
+#ifndef EVAL /* CMS compila z -DEVAL */
+ fprintf(stderr, "preverjam (%lld^2 + %lld^2 = %lf) = %lf^2\n", a, b, e, d);
+#endif
+ if ((int) d >= m && (int) d <= n && d == (int) d) {
+ for (int i = 0; i < u; i++) {
+ if ((r[i].a == a && r[i].b == b)
+ || (r[i].a == b && r[i].b == a)) {
+#ifndef EVAL
+ fprintf(stderr, "ogabno\n");
+#endif
+ goto ogabno;
+ }
+ }
+ r[u].a = a;
+ r[u++].b = b;
+ s++;
+ogabno:;
+ }
+ }
+#endif
+ for (a = 1; a <= n; a++)
+ for (b = 1; b <= n; b++)
+ for (c = 1; c <= n; c++)
+ if (a*a+b*b=c*c) {
+
+ }
+ fprintf(stdout, "%lld\n", s);
+ return 0;
+}