58, 76, 97, 104

1 files changed, 30 insertions, 0 deletions

diff --git a/euler97.c b/euler97.c
new file mode 100644
index 0000000..b0f55bc
--- /dev/null
+++ b/euler97.c
@@ -0,0 +1,30 @@
+#include <openssl/bn.h>
+
+static const unsigned char _7830457[3] = { 0x77, 0x7b, 0xb9 };
+static const unsigned char _2[1] = {2};
+static const unsigned char _28433[2] = {0x6f, 0x11};
+static const unsigned char _10000000000[5] = {0x02, 0x54, 0x0b, 0xe4, 0x00};
+
+int main()
+{
+	BIGNUM *b28433 = BN_bin2bn(_28433, 2, NULL);
+	BIGNUM *b2 = BN_bin2bn(_2, 1, NULL);
+	BIGNUM *b7830457 = BN_bin2bn(_7830457, 3, NULL);
+	BIGNUM *b10ten = BN_bin2bn(_10000000000, 5, NULL);
+
+	BN_CTX *ctx = BN_CTX_new();
+	BIGNUM *r = BN_new();
+	BIGNUM *r2 = BN_new();
+	BIGNUM *r3 = BN_new();
+	BN_mod_exp(r, b2, b7830457, b10ten, ctx);
+	BN_mul(r2, r, b28433, ctx);
+	BN_add(r3, r2, BN_value_one());
+	BN_mod(r, r3, b10ten, ctx);
+
+	unsigned char res[10];
+	int len = BN_bn2mpi(r, res);
+	for (int i = 0; i < len; i++)
+		printf("%02x", res[i]);
+
+	puts("");
+}