diff --git a/homework/chapter2/97.c b/homework/chapter2/97.c
index 0a22752..b18165a 100644
--- a/homework/chapter2/97.c
+++ b/homework/chapter2/97.c
@@ -20,26 +20,9 @@ float_bits float_i2f(int i) {
     s = 0x80000000U;
   }
 
-  int hb = 0, t = i;
-  if (t >> 16) {
-    t = t >> 16;
-    hb = hb + 16;
-  }
-  if (t >> 8) {
-    t = t >> 8;
-    hb = hb + 8;
-  }
-  if (t >> 4) {
-    t = t >> 4;
-    hb = hb + 4;
-  }
-  if (t >> 2) {
-    t = t >> 2;
-    hb = hb + 2;
-  }
-  if (t >> 1) {
-    t = t >> 1;
-    hb = hb + 1;
+  int hb = 30;
+  while (!(i >> hb)) {
+    hb = hb - 1;
   }
 
   i = i ^ (1 << hb);
diff --git a/homework/chapter2/README.md b/homework/chapter2/README.md
index b42bfe7..124ade3 100644
--- a/homework/chapter2/README.md
+++ b/homework/chapter2/README.md
@@ -33,6 +33,4 @@ b&=(a+x_{w-1}\cdot y+y_{w-1}\cdot x)\bmod 2^w\\
 先得到粗糙的结果 `(x >> 2) + ((x >> 2) << 1)`，再根据 `x & 3` 以及 $x$ 的符号（决定舍入方向）进行修正。
 
 ## 2.97
-注意以下细节：
-- 使用“折半递归法”求 $i$ 的有效位数可以避免对于所有 $2^{32}$ 个 `int` 检验花费极长的时间；
-- 在某些情况下，舍入会导致有效位数增加。
\ No newline at end of file
+注意在某些情况下，舍入会导致有效位数增加。
\ No newline at end of file