c++ - 接受两个转换字母输入的函数？

Question

我想知道如何创建一个函数来接受输入，例如“Computre”，或者任何可能的...“Cmoputer”、“romputeC”而不是“Computer”。

//This function would be something like this:
void ignore_switched_letters(char word[]);

int main(){//...}

void ignore_switched_letters(char word[]){
     //... code implimentation...
     char computer[9] = "Computer";
     int length = strlen(computer);
     for (int i = 0; i < length; ++i){
          if (word[i] == 'C'){ ....
          }
     }
}

Answer 1

我建议您将单词全部小写放在 std::string 中。那么你就有了standard library algorithms的力量可供您使用，包括 std::mismatch它返回两个范围不同的第一个位置。您可以检查是否存在两个彼此相反的不匹配。将其编写为比较两个单词的函数可能更灵活:

#include <string>
#include <algorithm>
#include <cassert>

bool compareIgnoreSingleSwitch(const std::string& word1, const std::string& word2) {
  if (word1.size() != word2.size())
    return false;

  auto mismatch1 = std::mismatch(word1.begin(), word1.end(), word2.begin());
  if (mismatch1.first == word1.end())
    return true;  // no mismatches

  auto mismatch2 
    = std::mismatch(std::next(mismatch1.first), word1.end(), std::next(mismatch1.second));

  if (mismatch2.first == word1.end())
    return false;  // only one mismatch, can't be a switch

  // check the two mismatches are inverse of each other
  if (*mismatch1.first != *mismatch2.second || *mismatch1.second != *mismatch2.first)
    return false;

  // ensure no more mismatches  
  return std::equal(std::next(mismatch2.first), word1.end(), std::next(mismatch2.second));
}

int main() {
  assert(compareIgnoreSingleSwitch("computer", "computer"));  // equal
  assert(compareIgnoreSingleSwitch("computer", "pomcuter"));  // one switch
  assert(!compareIgnoreSingleSwitch("computer", "aomxuter"));  // not a switch 
  assert(!compareIgnoreSingleSwitch("computer", "pomputer"));  // one mismatch
  assert(!compareIgnoreSingleSwitch("computer", "ocmupter"));  // two switches
  assert(!compareIgnoreSingleSwitch("computer", "compute"));  // different length    
}

Live demo.