sicily 1252. Defining Moment

#include<iostream>        //字符串模拟题
#include<string>
using namespace std;
string str;
int st,ed;
bool fit(int i,int j,string ss)
{
    if(i<st||j>ed)
        return false;
    for(int k=0;k<=j-i;++k)
        if(str[k+i]!=ss[k])
            return false;
    return true;
}
int main()
{
    int cases;
    cin>>cases;
    while(cases--)
    {
        string res;
        cin>>str;
        st=0;ed=str.size()-1;
        int tag;    

        //前缀
        if(fit(0,3,"anti"))
        {
            tag=1;
            res="against ";
            st+=4;    
        }
        else if(fit(0,3,"post"))
        {
            tag=1;
            res="after ";
            st+=4;
        }
        else if(fit(0,2,"pre"))
        {
            tag=1;
            res="before ";
            st+=3;
        }
        else if(fit(0,1,"re"))
        {
            tag=2;
            res=" again";
            st+=2;
        }
        else if(fit(0,1,"un"))
        {
            tag=1;
            res="not ";
            st+=2;
        }
        else
        {
            tag=0;
        }

        //后缀
        if(fit(ed-1,ed,"er"))
        {
            if(tag==0)
                res="one who "+str.substr(0,ed-2+1)+"s";
            else if(tag==1)
                res=res+"one who "+str.substr(st,ed-2-st+1)+"s";
            else
                res="one who "+str.substr(st,ed-2-st+1)+"s"+res;
        }
        else if(fit(ed-2,ed,"ing"))
        {
            if(tag==0)
                res="to actively "+str.substr(0,ed-3+1);
            else if(tag==1)
                res=res+"to actively "+str.substr(st,ed-3-st+1);
            else
                res="to actively "+str.substr(st,ed-3-st+1)+res;
        }
        else if(fit(ed-2,ed,"ize"))
        {
            if(tag==0)
                res="change into "+str.substr(0,ed-3+1);
            else if(tag==1)
                res=res+"change into "+str.substr(st,ed-3-st+1);
            else
                res="change into "+str.substr(st,ed-3-st+1)+res;
        }
        else if(fit(ed,ed,"s"))
        {
            if(tag==0)
                res="multiple instances of "+str.substr(0,ed-1+1);
            else if(tag==1)
                res=res+"multiple instances of "+str.substr(st,ed-1-st+1);
            else
                res="multiple instances of "+str.substr(st,ed-1-st+1)+res;
        }
        else if(fit(ed-3,ed,"tion"))
        {
            if(tag==0)
                res="the process of "+str.substr(0,ed-4+1)+"ing";
            else if(tag==1)
                res=res+"the process of "+str.substr(st,ed-4-st+1)+"ing";
            else
                res="the process of "+str.substr(st,ed-4-st+1)+"ing"+res;
        }
        else
        {
            if(tag==0)
                res=str;
            else if(tag==1)
                res=res+str.substr(st,ed-st+1);
            else 
                res=str.substr(st,ed-st+1)+res;
        }
        

        cout<<res<<endl;
    }
    return 0;
}