ACTUALLY fix strongPseudoPrime2

1 files changed, 10 insertions, 0 deletions

diff --git a/bigint.cpp b/bigint.cpp
index 0d2a72b..83d00c1 100644
--- a/bigint.cpp
+++ b/bigint.cpp
@@ -542,6 +542,16 @@ bool Bigint::odd() const {
 	return !even();
 }
 
+int Bigint::trailingZeros() const {
+	if(digits.size()==0)throw domain_error("trailingZeros called on zero bigint");
+	int res=0;
+	for(digit_t dig : digits){
+		if(dig==0)res+=digit_bits;
+		else return res+__builtin_ctz(dig);
+	}
+	assert(false); //bigint is not consistent: zero while digits is not empty!
+}
+
 //Produces a string with the bytes of the mantissa in little-endian order.
 string Bigint::serialiseMantissa() const {
 	string s;