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最新推荐文章于 2024-08-14 21:30:58 发布

原创最新推荐文章于 2024-08-14 21:30:58 发布 · 687 阅读

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本文介绍了一个C++算法实现，用于优化字符串比较操作，通过比较字符串的左右部分来减少不必要的字符比较次数。包括从左到右和从右到左两种情况下的优化策略，旨在提高程序效率。

class Solution {
public:
   int minCut(string s) {
   // Start typing your C/C++ solution below
   // DO NOT write int main() function
   int a = froml(s);
   int b = fromr(s);
   return a>b?b:a;
   }

   int froml(string s){
   int length = s.length();

   if (1 == length) return 0;

   char * pc = new char[length+1];
   strcpy(pc,s.c_str());

   int len = length-1;
   char* pbc = pc;
   char* pec = pc+len;
   int count = 0;
   bool flag = false;

   while(1){
   int l = (pec - pbc)/2;
   int i = 0;
   for (;i<=l ;i++){
   if(*(pbc+i) != *(pec-i)){
   flag = false;
   break;
   }
   flag = true;
   }
   if(!flag){
   pec--;
   }else{
   if(pec != pc + len){
   count++;
   pbc = pec + 1;
   pec = pc + len;
   }else{
   break;
   }
   }
   }

   return count;
   }
   int fromr(string s){
   int length = s.length();

   if (1 == length) return 0;

   char * pc = new char[length+1];
   strcpy(pc,s.c_str());

   int len = length-1;

   //reverse
   int j = 0;
   for (;j<=len/2;j++){
   char temp = pc[j];
   pc[j] = pc[len-j];
   pc[len-j] = temp;
   }

   char* pbc = pc;
   char* pec = pc+len;
   int count = 0;
   bool flag = false;

   while(1){
   int l = (pec - pbc)/2;
   int i = 0;
   for (;i<=l ;i++){
   if(*(pbc+i) != *(pec-i)){
   flag = false;
   break;
   }
   flag = true;
   }
   if(!flag){
   pec--;
   }else{
   if(pec != pc + len){
   count++;
   pbc = pec + 1;
   pec = pc + len;
   }else{
   break;
   }
   }
   }

   return count;
   }

};