implemented ostream output op for integer.cpp

integer.cpp

@@ -2,6 +2,8 @@
 #include <cassert>
 #include <cstddef>
 #include <iostream>
+#include <sstream>
+#include <string>
 #define todo(msg)                                                              \
   std::cerr << msg << std::endl;                                               \
   assert(false);
@@ -115,6 +117,12 @@ public:
     ret %= rhs;
     return ret;
   }
+  friend Integer operator%(Integer const &lhs, byte rhs) {
+    if (lhs.size == 0 || lhs.bytes == nullptr) {
+      return 0;
+    }
+    return lhs.bytes[0] % rhs;
+  }
   friend Integer operator-(Integer const &val) {
     Integer ret = val;
     ret.isNegative = !ret.isNegative;
@@ -135,10 +143,24 @@ public:
   }
 
   friend std::ostream &operator<<(std::ostream &lhs, Integer const &rhs) {
-    Integer discard = rhs;
+    if (rhs == 0) {
+      lhs << 0;
+      return lhs;
+    }
 
+    Integer discard = rhs;
+    std::stringstream to_output{};
+    while (discard != 0) {
+      to_output << discard % 10;
+      discard /= 10;
+    }
+    std::string out;
+    to_output >> out;
+    std::reverse(out.begin(), out.end());
+    lhs << out;
     return lhs;
   }
+
   explicit operator unsigned long() {
     unsigned long ret = 0;
     for (std::size_t i = 0; i < std::min(size, sizeof(unsigned long)); i++) {