Lưu ý: Các code mẫu dưới đây chỉ mang tính tham khảo và có thể không AC được bài tập này

Code mẫu của flashmt

#include <iostream>
#include <string>
#include <cctype>
#include <cmath>
using namespace std;

int checkType(string s)
{
    int res = 0;
    for (int i = 0; i < s.size(); i++)
        if (s[i] >= '0' && s[i] <= '9') res |= 1;
        else
            if (tolower(s[i]) >= 'a' && tolower(s[i]) <= 'z') res |= 2;
    return res;
}

double getSum(string s)
{
    double res = 0, x = 0, power = 1;
    s += ' ';
    for (int i = 0, dotted = 0, sign = 1; i < s.size(); i++)
        if (s[i] == ' ') res += x/power*sign, power = 1, x = 0, dotted = 0, sign = 1;
        else 
            if (s[i] == '-') sign = -1;
            else
                if (s[i] == '.') dotted = 1;
                else x = x * 10 + s[i] - '0', power *= (dotted > 0? 10: 1);
    return res;
}

string concatStr(string s)
{
    string res = "";
    for (int i = 0; i < s.size(); i++) 
        if (s[i] != ' ') res += s[i];
    return res;
}

int main()
{
    string s;
    while (getline(cin,s))
    {
        if (s=="?") break;

        int type = checkType(s);

        if (type == 3) puts("Error!");
        else
            if (type == 1) printf("%.6lf\n",getSum(s));
            else cout << concatStr(s) << endl;
    }
}

Code mẫu của ladpro98

const   fi='';
var     inp:text;
        s:string;
        i,l,code:longint;
        t,sum:extended;
        err:boolean;
begin
        assign(inp,fi);reset(inp);
        while true do
        begin
                readln(inp,s);
                err:=false;
                while s[1]=' ' do delete(s,1,1);
                if s[1]='?' then break;
                if s[1] in ['A'..'z'] then
                begin
                        for i:=1 to length(s) do
                        if (s[i]<>' ') and (not (s[i] in ['A'..'z'])) then
                        begin
                                writeln('Error!');
                                err:=true;
                                break;
                        end;
                        if err then continue;
                        for i:=length(s) downto 1 do
                        if s[i]=' ' then delete(s,i,1);
                        writeln(s);
                        continue;
                end;
                if (s[1]='.') or (s[1]='-') or (s[1] in ['0'..'9']) then
                begin
                        sum:=0;
                        for i:=length(s) downto 2 do if (s[i]=' ') and (s[i-1]=' ') then delete(s,i,1);
                        if s[length(s)]<>' ' then s:=s+' ';
                        l:=1;
                        for i:=1 to length(s) do
                        if s[i]=' ' then
                        begin
                                Val(copy(s,l,i-l),t,code);
                                l:=i+1;
                                if code<>0 then
                                begin
                                        writeln('Error!');
                                        err:=true;
                                        break;
                                end;
                                sum:=sum+t;
                        end;
                        if err then continue;
                        writeln(sum:0:6);
                        continue;
                end;
                writeln('Error!');
        end;
        close(inp);
end.

Code mẫu của RR

//#pragma comment(linker, "/STACK:66777216")
#include <iomanip>
#include <sstream>
#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <string>
#include <deque>
#include <complex>
#include <bitset>

#define FOR(i,a,b) for(int i=(a),_b=(b); i<=_b; ++i)
#define FORD(i,a,b) for(int i=(a),_b=(b); i>=_b; --i)
#define REP(i,a) for(int i=0,_a=(a); i<_a; ++i)
#define ll long long
#define F first
#define S second
#define PB push_back
#define MP make_pair
#define DEBUG(x) cout << #x << " = " << x << endl;
#define PR(a,n) cout << #a << " = "; FOR(i,1,n) cout << a[i] << ' '; puts("");
#define PR0(a,n) cout << #a << " = "; REP(i,n) cout << a[i] << ' '; puts("");
using namespace std;

const double PI = acos(-1.0);

char s[100111];

bool allNum() {
    REP(i,strlen(s))
    if (s[i] != ' ')
    if (s[i] != '-' && s[i] != '.')
        if (s[i] < '0' || s[i] > '9') return false;
    return true;
}

bool allChar() {
    REP(i,strlen(s))
    if (s[i] != ' ')
    if (s[i] < 'a' || s[i] > 'z')
    if (s[i] < 'A' || s[i] > 'Z') return false;
    return true;
}

int main() {
//    freopen("input.txt", "r", stdin);
//    freopen("output.txt", "w", stdout);
    while (gets(s)) {
        if (s[0] == '?') break;
        if (allNum()) {
            istringstream sin(s);
            long double res = 0.0, x;
            while (sin >> x) {
                res += x;
            }
            cout << (fixed) << setprecision(6) << res << endl;
        }
        else if (allChar()) {
            istringstream sin(s);
            string res = "", x;
            while (sin >> x) {
                res += x;
            }
            cout << res << endl;
        }
        else puts("Error!");
    }
    return 0;
}

Code mẫu của hieult

#include <set>
#include <map>
#include <cmath>
#include <deque>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <cstdlib>
#include <cstring>
#include <sstream>
#include <iostream>
#include <algorithm>

using namespace std;

#define Rep(i,n) for(typeof(n) i = 0; i < (n); ++i)
#define Repd(i,n) for(typeof(n) i = (n)-1; i >= 0; --i)
#define For(i,a,b) for(typeof(b) i = (a); i <= (b); ++i)
#define Ford(i,a,b) for(typeof(a) i = (a); i >= (b); --i)

bool isword(string s) {
    int len = s.length();
    Rep(i, len) if (!isalpha(s[i])) return false;
    return true;
}

bool isnumber(string s) {
    int minus = 0, dot = 0, posminus = -1, posdot = -1;

    int len = s.length();
    Rep(i, len) {
        if (s[i] == '-') {
            ++minus;
            posminus = i;
        }
        else if (s[i] == '.') {
            ++dot;
            posdot = i;
        }
        else if (!isdigit(s[i])) return false;
    }

    if (minus > 1 || dot > 1) return false;
    if (minus == 1 && posminus != 0) return false;

    return true;
}

double convert(string s) {
    stringstream ss;
    ss << s;
    double r;
    ss >> r;
    return r;
}

string line, s;
vector<string> a;

void process() {
    int n = a.size();

    if (n == 0) {
        puts("Error!");
        return;
    }

    double sum = 0;
    string cat = "";
    bool allnumber = true, allword = true;

    Rep(i, n) {
        if (isnumber(a[i])) {
            sum += convert(a[i]);
            allword = false;
        }
        else if (isword(a[i])) {
            cat = cat + a[i];
            allnumber = false;
        }
        else {
            puts("Error!");
            return;
        }
    }

    if (allword) cout << cat << endl;
    else if (allnumber) printf("%.6lf\n", sum);
    else puts("Error!");
}

int main() {
    while (getline(cin, line) && line != "?") {
        a.clear();
        istringstream iss(line);
        while (iss >> s) a.push_back(s);
        process();
    }
    return 0;
}

Code mẫu của skyvn97

program test;
uses crt;
var
   s,sb,t:string;
   a,r:real;
   b,ck:integer;
   i,j:integer;
   fst:boolean;
   num:boolean;
   str:boolean;
   err:boolean;
function ckstr(s:string):integer;
         var
            i:integer;
         begin
              b:=0;
              val(s,a,b);
              if (b<>0) then
                 begin
                      for i:=1 to length(s) do
                          begin
                               if ord('A')>ord(s[i]) then begin ckstr:=-1; exit; end;
                               if ord('z')<ord(s[i]) then begin ckstr:=-1; exit; end;
                               if (ord('Z')<ord(s[i])) and (ord('a')>ord(s[i])) then
                                  begin ckstr:=-1; exit; end;
                          end;
                      ckstr:=1; exit;
                 end
              else begin ckstr:=0; exit; end;
         end;
begin
     repeat
           readln(s);
           if (length(s)<>1) or (s[1]<>'?') then
              begin
                   while (pos('  ',s)<>0) do delete(s,pos('  ',s),1);
                   fst:=true;
                   err:=false;
                   str:=false;
                   num:=false;
                   r:=0;
                   t:='';
                   if s[1]<>' ' then s:=' '+s;
                   if s[length(s)]<>' ' then s:=s+' ';
                   while pos(' ',s)<>length(s) do
                         begin
                              i:=pos(' ',s);
                              for j:=i+1 to length(s) do
                                  if s[j]=' ' then break;
                              sb:=copy(s,i+1,j-i-1);
                              ck:=ckstr(sb);
                              if ck<0 then begin err:=true; break; end;
                              if ck=0 then
                                 begin
                                      if fst then
                                         begin
                                              fst:=false;
                                              num:=true;
                                              r:=a;
                                         end
                                      else begin
                                                if str then err:=true
                                                else r:=r+a;
                                           end;
                                 end;
                              if ck>0 then
                                 begin
                                      if fst then
                                         begin
                                              fst:=false;
                                              str:=true;
                                              t:=sb;
                                         end
                                      else begin
                                                if num then err:=true
                                                else t:=t+sb;
                                           end;
                                 end;
                              if err then break;
                              delete(s,i,j-i);
                         end;
                   if err then
                      begin
                           writeln('Error!');
                           continue;
                      end;
                   if num then
                      begin
                           writeln(r:0:6);
                           continue;
                      end;
                   if str then
                      begin
                           writeln(t);
                           continue;
                      end;
              end
           else halt;
     until false;
end.