Data commit

Task/Summarize-primes/C/summarize-primes.c

@@ -0,0 +1,55 @@
+#include <stdbool.h>
+#include <stdio.h>
+
+bool is_prime(int n) {
+    int i = 5;
+
+    if (n < 2) {
+        return false;
+    }
+
+    if (n % 2 == 0) {
+        return n == 2;
+    }
+    if (n % 3 == 0) {
+        return n == 3;
+    }
+
+    while (i * i <= n) {
+        if (n % i == 0) {
+            return false;
+        }
+        i += 2;
+
+        if (n % i == 0) {
+            return false;
+        }
+        i += 4;
+    }
+
+    return true;
+}
+
+int main() {
+    const int start = 1;
+    const int stop = 1000;
+
+    int sum = 0;
+    int count = 0;
+    int sc = 0;
+    int p;
+
+    for (p = start; p < stop; p++) {
+        if (is_prime(p)) {
+            count++;
+            sum += p;
+            if (is_prime(sum)) {
+                printf("The sum of %3d primes in [2, %3d] is %5d which is also prime\n", count, p, sum);
+                sc++;
+            }
+        }
+    }
+    printf("There are %d summerized primes in [%d, %d)\n", sc, start, stop);
+
+    return 0;
+}