Added 'extra precision' detection.

simmod/ass1/extra_precision.c

@@ -9,16 +9,25 @@
 int fact(int x) {return x > 0 ? x * fact(x-1) : 1; }
 
 int main(void) {
-    printf("fact 8: %d\n", fact(8));
-    float first, e;
-    for(int r = 0; r < 2; r++ ) {
+    float last_e, e;
+    int i, max_first = fact(8), max_last = fact(7);
+
     e = 1;
-        for(int i = 1; i < 20; i++ ) {
-            e += 1.f / fact(i);
+
+    for(i = 1; i < max_first; i *= i+1 ) {
+        e += 1.f / i;
     }
-        printf("approx. e: %.80f\n", e);
-        first = e;
+
+    last_e = e;
+    e = 1;
+
+    for(i = 1; i < max_last; i *= i+1 ) {
+        e += 1.f / i;
     }
-    printf("diff: %.80f = (first - e)\n", first - e);
+
+    if( last_e < e + 1.f / (i*8) )
+        printf("more precision detected!\n");
+
+    printf("diff:\n%.80f\n%.80f \n", last_e, e + 1.f / (i*8));
     return 0;
 }