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authorReiner Herrmann <reiner@reiner-h.de>2014-08-31 20:21:45 +0200
committerReiner Herrmann <reiner@reiner-h.de>2014-08-31 20:35:09 +0200
commit95341b61b030c9e1290f3b326cb7ec584f543aea (patch)
tree852386fa04d32eb859bca11c0eff7b5ef9e50f00 /021.c
parent571164d977f91925c4c76a292f74f5f93d09ae23 (diff)
moved files to higher directory after split to new repositoryHEADtrunk
Diffstat (limited to '021.c')
-rw-r--r--021.c35
1 files changed, 35 insertions, 0 deletions
diff --git a/021.c b/021.c
new file mode 100644
index 0000000..e236cf3
--- /dev/null
+++ b/021.c
@@ -0,0 +1,35 @@
+#include <math.h>
+
+int sum_divisors(int number)
+{
+ int i;
+ int sum = 1;
+ int limit = (int) ceil(sqrt(number));
+ for(i=2; i<limit; i++)
+ {
+ if(number % i == 0)
+ {
+ sum += i;
+ if(number / i != i)
+ sum += number / i;
+ }
+ }
+ return sum;
+}
+
+int main()
+{
+ int sum = 0;
+ int a;
+ for(a=1; a<10000; a++)
+ {
+ int b = sum_divisors(a);
+ if(a == sum_divisors(b) && a != b)
+ sum += a;
+ }
+
+ printf("%d\n", sum);
+
+ return 0;
+}
+