PATA 1071 Speech Patterns.

#include <bits/stdc++.h>
using namespace std;
bool check(char c)//检查是否为字母或数字
{
	if(c>=‘A‘&&c<=‘Z‘||c>=‘a‘&&c<=‘z‘||c>=‘0‘&&c<=‘9‘)
		return true;
	else
		return false;
}
int main()
{
	map<string,int> count;
	string str;
	getline(cin,str);
	int i = 0;
	while(i<str.length())
	{
		string word;
		while(i<str.length()&&check(str[i]))
		{
			if(str[i]>=‘A‘&&str[i]<=‘Z‘){  //大写统一改为小写
				str[i] += (‘a‘-‘A‘);
			}
			word += str[i]; //字符拼接 +
			i++;
		}
		if(word != ""){
			if(count.find(word)==count.end())	count[word]=1;  //这单词还没出现过，计数为1
			else count[word]++;
		}
		while(i<str.length()&&!check(str[i]))  //遇到其它字符跳过
		{
			i++;
		}
	}
	string ans;
	int  MAX=0;
	for(map<string,int>::iterator it=count.begin();it != count.end();it++)  //只能用!=，而不能用<end()
	{
		if(it->second>MAX)
		{
			ans = it->first;
			MAX = it->second;
		}
	}
	cout<<ans<<" "<<MAX<<endl;
	return 0;

}

原文地址：https://www.cnblogs.com/qiangz/p/8552382.html