From 9a9b1af434d910494527c631ef5e951cccea7147 Mon Sep 17 00:00:00 2001
From: batzor <32958247+batzor@users.noreply.github.com>
Date: Wed, 5 Jun 2024 18:36:22 +0900
Subject: [PATCH] feat(math): impl remove zeros for sparse univariate poly

---
 .../univariate/univariate_polynomial_ops.h         |  4 ++--
 .../univariate/univariate_sparse_coefficients.h    | 14 +++++++-------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/tachyon/math/polynomials/univariate/univariate_polynomial_ops.h b/tachyon/math/polynomials/univariate/univariate_polynomial_ops.h
index dd317f3d6c..f33573c22a 100644
--- a/tachyon/math/polynomials/univariate/univariate_polynomial_ops.h
+++ b/tachyon/math/polynomials/univariate/univariate_polynomial_ops.h
@@ -832,7 +832,7 @@ class UnivariatePolynomialOp<UnivariateSparseCoefficients<F, MaxDegree>> {
     }
 
     c.coefficients_ = S(std::move(c_terms));
-    c.coefficients_.RemoveHighDegreeZeros();
+    c.coefficients_.RemoveZeros();
   }
 
   static void DoMul(const UnivariatePolynomial<S>& a,
@@ -861,7 +861,7 @@ class UnivariatePolynomialOp<UnivariateSparseCoefficients<F, MaxDegree>> {
     }
     pdqsort(c_terms.begin(), c_terms.end());
     c.coefficients_ = S(std::move(c_terms));
-    c.coefficients_.RemoveHighDegreeZeros();
+    c.coefficients_.RemoveZeros();
   }
 };
 
diff --git a/tachyon/math/polynomials/univariate/univariate_sparse_coefficients.h b/tachyon/math/polynomials/univariate/univariate_sparse_coefficients.h
index fa62edbfa1..75f1ba702a 100644
--- a/tachyon/math/polynomials/univariate/univariate_sparse_coefficients.h
+++ b/tachyon/math/polynomials/univariate/univariate_sparse_coefficients.h
@@ -104,13 +104,13 @@ class UnivariateSparseCoefficients {
   constexpr explicit UnivariateSparseCoefficients(
       const std::vector<Term>& terms)
       : terms_(terms) {
+    RemoveZeros();
     CHECK_LE(Degree(), kMaxDegree);
-    RemoveHighDegreeZeros();
   }
   constexpr explicit UnivariateSparseCoefficients(std::vector<Term>&& terms)
       : terms_(std::move(terms)) {
+    RemoveZeros();
     CHECK_LE(Degree(), kMaxDegree);
-    RemoveHighDegreeZeros();
   }
 
   constexpr static UnivariateSparseCoefficients CreateChecked(
@@ -289,12 +289,12 @@ class UnivariateSparseCoefficients {
     return &it->coefficient;
   }
 
-  void RemoveHighDegreeZeros() {  // Fix to RemoveZeros
-    while (!IsZero()) {
-      if (terms_.back().coefficient.IsZero()) {
-        terms_.pop_back();
+  void RemoveZeros() {
+    for(auto it = terms_.begin();it != terms_.end();) {
+      if (it->coefficient.IsZero()) {
+        it = terms_.erase(it);
       } else {
-        break;
+        ++it;
       }
     }
   }