为何第三个点会RE？

本地第三个点可以成功运行，然而洛谷上就 RE，不是很懂。

第三个点数据：\texttt{Chen Junao is no so clever .}

#include<bits/stdc++.h>
using namespace std;
map<string,int> f;
char sum[6][3];
char ans[20];
int main(){
    f["zero"]     =0;
    f["one"]      =1;
    f["two"]      =2;
    f["three"]    =3;
    f["four"]     =4;
    f["five"]     =5;
    f["six"]      =6;
    f["seven"]    =7;
    f["eight"]    =8;
    f["nine"]     =9;
    f["ten"]      =10;
    f["eleven"]   =11;
    f["twelve"]   =12;
    f["thirteen"] =13;
    f["fourteen"] =14;
    f["fifteen"]  =15;
    f["sixteen"]  =16;
    f["seventeen"]=17;
    f["eighteen"] =18;
    f["ninteen"]  =19;
    f["twenty"]   =20;

    f["a"]        =1;
    f["another"]  =1;
    f["first"]    =1;
    f["both"]     =2;
    f["second"]   =2;
    f["third"]    =3;

    string k;
    map<string,int>::iterator it;
    for(int i=0;i<6;i++){
        cin>>k;
        it=f.find(k);
        if(it==f.end()) sum[i][0]='0',sum[i][1]='0',sum[i][2]='\0';
        else sprintf(sum[i],"%02d",f[k.c_str()]*f[k.c_str()]%100);
    }
    cin>>k;
    for(int i=0;i<6;i++){
        for(int j=0;j<i;j++){
            if(strcmp(sum[j],sum[i])>0) swap(sum[j],sum[i]);
        }
    }
    for(int i=0;i<6;i++){
        strcat(ans,sum[i]);
    }
    int p=0;
    while(ans[p]=='0'||ans[p]=='\0') p++;
    if(p>=12){
        cout<<0;
        return 0;
    }
    for(int i=p;i<12;i++)
        cout<<ans[i];
}