ZOJ 1698 Easier Done Than Said?

#include <cstdio>#include <cstring>#include <cstdlib>#include <vector>#include <cmath>#include <iostream>#include <algorithm>#include <functional>#include <string>#include <map>using namespace std;bool isvowels(char c){    if(c=='a'||c=='e'||c=='i'||c=='o'||c=='u')        return true;    return false;}int main(){    bool r1,r2,r3;    char str[100];    while(gets(str))    {        if(strcmp(str,"end")==0)            break;        int len=strlen(str);        r1=false;        r2=r3=true;        for(int i=0;i<len;i++)        {            if(str[i]=='a'||str[i]=='e'||str[i]=='i'||str[i]=='o'||str[i]=='u')                r1=true;            if(i+2<len)            {                if(isvowels(str[i])&&isvowels(str[i+1])&&isvowels(str[i+2]))                    r2=false;                if(!isvowels(str[i])&&!isvowels(str[i+1])&&!isvowels(str[i+2]))                    r2=false;            }            if(i+1<len && !(str[i]=='e'||str[i]=='o') )            {                if(str[i]==str[i+1])                    r3=false;            }        }        if(r1&&r2&&r3)            printf("<%s> is acceptable.\n",str);        else            printf("<%s> is not acceptable.\n",str);    }    return 0 ;}