绋嬪簭鐨勬満鍣ㄧ骇琛ㄧず

Posted 2020-06-18

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閫昏緫鍙崇Щ涓庣畻鏈彸绉?

閫昏緫鍙崇Щ锛氶珮浣嶈ˉ0

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濡傛灉鍦ㄤ竴涓?2锛坵锛変綅鏈哄櫒涓紝绉讳綅鎿嶄綔鐨勪綅鏁?k)>32鏃舵€庝箞鍔烇紵锛屼护k=(k)mod(w)銆?/p>

 

  缁冧範棰?2.11銆€鍦ㄧ粌涔犻 2.10 涓殑inplace_swap鍑芥暟鐨勫熀纭€涓婏紝浣犲喅瀹氬啓涓€娈典唬鐮侊紝瀹炵幇灏嗕竴涓暟 缁勪腑鐨勫厓绱犲ご灏句袱绔緷娆″璋冦€備綘鍐欏嚭涓嬮潰杩欎釜鍑芥暟 锛?/p>

1 void reverse_array(int a[], int cnt) { 2 int first, last; 3 for (first = 0, last = cnt-1; 4 first <= last; 5 first++,last--) 6 inplace_swap(&a[first], &a[last]); 7 }

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http://c-faq.com/expr/xorswapexpr.html

A: first鍜宭ast鐨勫€肩浉绛変簡锛屼负k锛堝浜庡鏁颁釜鍏冪礌锛?k+1锛?/p>

B:瀵逛簬xor_swap杩欎釜鍑芥暟锛寈鍜寉鏄笉鑳藉鎸囧悜鍚屼竴涓湴鍧€鐨? 棣栧厛灏辨槸涓湭瀹氫箟琛屼负.

鍙互鍙傜湅 http://c-faq.com/expr/xorswapexpr.html 

鍏舵灏辩畻涓嶆槸鏈畾涔夎涓猴紝姣斿璇碈璇█涓ユ牸瑙勫畾浜嗘眰鍊煎緱椤哄簭涔熶竴鏍蜂細鍑虹幇闂锛岀涓€姝ュ氨鎶妜鍜寉鍙樻垚0浜?/p>

C:淇敼涓篺or(first = 0, last = cnt; first < last, first++, last--)灏卞彲浠ヤ簡銆?/p>

銆€涔犻2.25鑰冭檻涓嬪垪浠ｇ爜锛岃繖娈典唬鐮佽瘯鍥捐绠楁暟缁刟涓墍鏈夊厓绱犵殑鍜岋紝鍏朵腑鍏冪礌鐨勬暟閲忕敱鍙傛暟length缁欏嚭銆?/p>

1 /* WARNING: This is buggy code */

2 float sum_elements(float a[], unsigned length) {

3 int i;

4 float result = 0;

6 for (i = 0; i <= length-1; i++)

7 result += a[i];

8 return result;

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answer锛歭ength-1浼氭湁婧㈠嚭锛屾墍浠ユ敼涓?< length
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unsigned i
for (i = 0; i < length; ++i)

****************************************************************

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