Co-authored-by: sigonasr2 <sigonasr2@gmail.com>

archives/10/src/main.c

@@ -0,0 +1,31 @@
+#include <stdio.h>
+#include "utils.h"
+
+/*
+The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17.
+
+Find the sum of all the primes below two million.
+
+https://projecteuler.net/problem=10
+*/
+int main(int argc,char**argv) {
+    FILE*f=fopen("archives/primegenerator/primes","r");
+    long sum=0;
+    int ch=' ';
+    while ((ch=fgetc(f))!='{');
+    while (true) {
+        int digit=0;
+        while ((ch=fgetc(f))!=',') {
+            digit*=10;
+            digit+=ch-'0';
+        }
+        if (digit>=2000000) {
+            break;
+        } else {
+            sum+=digit;
+        }
+    }
+    fclose(f);
+    printf("\n\nThe sum of all primes below 2000000 is %ld",sum);
+    return 0;
+}

archives/10/src/utils.h

@@ -0,0 +1,7 @@
+#define true 1
+#define false 0
+#define boolean char
+struct String{
+    int length;
+    char*str;
+};

src/main.c

@@ -2,30 +2,30 @@
 #include "utils.h"
 
 /*
-A Pythagorean triplet is a set of three natural numbers, a < b < c, for which,
+The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17.
 
-a2 + b2 = c2
-For example, 32 + 42 = 9 + 16 = 25 = 52.
+Find the sum of all the primes below two million.
 
-There exists exactly one Pythagorean triplet for which a + b + c = 1000.
-Find the product abc.
-
-https://projecteuler.net/problem=9
+https://projecteuler.net/problem=10
 */
 int main(int argc,char**argv) {
-    int a=1;
-    int b=2;
-    int c=997;
-    int sum=0;
-    for (b=2;b<c;b++) {
-        for (a=1;a<b;a++) {
-            int tempC=1000-a-b;
-            if (a*a+b*b==tempC*tempC) {
-                printf("Pythagorean triplet of %d^2+%d^2=%d^2 works for %d+%d+%d=1000\n",a,b,tempC,a,b,tempC);
-                printf("Product is %d",a*b*tempC);
-                return 0;
-            }
+    FILE*f=fopen("archives/primegenerator/primes","r");
+    long sum=0;
+    int ch=' ';
+    while ((ch=fgetc(f))!='{');
+    while (true) {
+        int digit=0;
+        while ((ch=fgetc(f))!=',') {
+            digit*=10;
+            digit+=ch-'0';
+        }
+        if (digit>=2000000) {
+            break;
+        } else {
+            sum+=digit;
         }
     }
+    fclose(f);
+    printf("\n\nThe sum of all primes below 2000000 is %ld",sum);
     return 0;
 }