public OnPlayerCommandText(playerid, cmdtext[])
{
  new Float:tmp2;
             new Float:tmp3;
  new name[256];
  new weapon1, ammo1, weapon2, ammo2, weapon3, ammo3, weapon4, ammo4, weapon5, ammo5, weapon6, ammo6;
             new string[256];
             new index, cmd[128];
     cmd = strtok(cmdtext, index);
     if (!strcmp("/gpi",cmd,true,8))
  {
         new tmp[128];
         tmp = strtok(cmdtext, index);
         if(!strlen(tmp)  || !IsNumeric(tmp))
   {
             return SendClientMessage(playerid,0xAAFF00AA,"Юзай: /command [playerid]");
         }
         else {
             new id=strval(tmp);
             if(!IsPlayerConnected(id))
    {
                 return SendClientMessage(playerid,0xAAFF00AA,"Нипадключон ыгрок");
    }
             else
    {
     GetPlayerHealth(id, tmp3);
     GetPlayerName(id, name, 24);
     GetPlayerWeaponData(id, 8, weapon1, ammo1);
     GetPlayerWeaponData(id, 2, weapon2, ammo2);
     GetPlayerWeaponData(id, 3, weapon3, ammo3);
     GetPlayerWeaponData(id, 4, weapon4, ammo4);
     GetPlayerWeaponData(id, 5, weapon5, ammo5);
     GetPlayerWeaponData(id, 6, weapon6, ammo6);
     format(string, sizeof(string), "%s:HP:%f, Гранаты:%d, Пистолеты:%d, Дробовики:%d, П-Автоматы:%d, Автоматы:%d, Винтовка:%d", name, tmp3, ammo1, ammo2, ammo3, ammo4, ammo5, ammo6);
                 SendClientMessage(playerid,0xAAFF00AA,string);
             }
         }
         return 1;
     }
     return 0;
}

strtok(const string[], &index)
{
     new length = strlen(string);
     while ((index < length) && (string[index] <= ' '))
     {
         index++;
     }
     new offset = index;
     new result[20];
     while ((index < length) && (string[index] > ' ') && ((index - offset) < (sizeof(result) - 1)))
     {
         result[index - offset] = string[index];
         index++;
     }
     result[index - offset] = EOS;
     return result;
}

//-----
stock IsNumeric(const string[]) { // by DracoBlue
     new length=strlen(string);
     if (length==0) return false;
     for (new i = 0; i < length; i++) {
         if (
         (string[i] > '9' || string[i] < '0' && string[i]!='-' && string[i]!='+') // Not a number,'+' or '-'
         || (string[i]=='-' && i!=0)                    // A '-' but not at first.
         || (string[i]=='+' && i!=0)                    // A '+' but not at first.
         ) return false;
     }
     if (length==1 && (string[0]=='-' || string[0]=='+')) return false;
     return true;
}

for(new i; i < MAX_PLAYERS; i++){
//условие
}

for(new i=0; i<MAX_PLAYERS; i++)
{
  for(new j=0; j<MAX_VEHICLES; j++)
  {
   ....
  }
}

for(new i=0; i<10; i++)
{
while(new j=0; i < 7; j++)
{
new string[256];
format(string,sizeof(string),"J=%d",j);
SendClientMessage(playerid,0xFFFFFFAA,string);
}
}

IsNumeric(const string[])
{
    for (new i = 0, j = strlen(string); i < j; i++)
    {
  if (string[i] > '9' || string[i] < '0') return 0;
    }
    return 1;
}