added init constructor

src/bigint.cpp

@@ -34,6 +34,10 @@ BigInt::BigInt(long val):
     mpz_set_si(data, val);
 }
 
+BigInt::BigInt(char item, unsigned int size, int base = 2):
+    BigInt(std::string(size, item),base) {
+}
+
 std::string BigInt::getString(int base) const {
     char *str = mpz_get_str(nullptr, base, data);
     return str;

src/bigint.h

@@ -26,6 +26,7 @@ public:
     BigInt(const std::string &imput, int base = 10);
 //    BigInt(const char * str, int base = 10);
     BigInt(long val);
+    BigInt(char item, unsigned int size, int base);
 
     std::string getString(int base = 10) const;
     ~BigInt();