Time complexity

[riyadhhossain01]

Is it possible to make a time complexity function which will calculate the average running time of the following code:

#include <iostream>
#include <chrono>
using namespace std;

struct uinput{
string text;
int time;
};
char randChar(){
char start;
int r = rand();
if(r % 2 == 0)
start = 'A';
else
start = 'a';
start += r % 26;
return start;
}
string genString(int i){
string ret;
for(;i > 0;i--){
ret.push_back(randChar());
}
return ret;
}
uinput getInput(){
uinput inp;
chrono::steady_clock::time_point t1 = chrono::steady_clock::now();
getline(cin,inp.text);
chrono::steady_clock::time_point t2 = chrono::steady_clock::now();
chrono::milliseconds elapsed = chrono::duration_cast<chrono::milliseconds>(t2 - t1);
inp.time = elapsed.count();
return inp;
}
int penalty(string s1, string s2){
int pen = 0;
int len = max(s1.length(),s2.length());
for(int i = 0;i < len;i++){
char c1,c2;
c1 = i >= s1.length()?' ':s1[i];
c2 = i >= s2.length()?' ':s2[i];
pen += abs(c1 - c2);
}
return pen;
}
uinput takeTurn(int points, int length, string text){
cout << "Your current points " << points;
cout << ", just type [" << length << "] -> " << text << ": ";
return getInput();
}
void start(){
int points = 1000, level = 0, combo = 0;
while(points > 0){
int len = 5 + level;
int interval = 5000 - (250 * level);
string text = genString(len);
uinput in = takeTurn(points,len,text);
if(!in.text.compare("end"))
break;

cout << in.time << " milliseconds, ";
bool madeit;
if(in.time <= interval){
cout << "you made it";
madeit = true;
}
else{
cout << "you *failed* it";
madeit = false;
}
cout << " within the interval of " << interval << "..." << endl;
int offset = penalty(text,in.text);
int pen = offset * (madeit?1:2);
if(offset){
cout << "String offset is " << offset;
cout << ", your penalty is " << pen << "..." << endl;
}
points -= pen;
if(pen){
if(combo >= 0)
combo = -1;
else
combo--;
}
else if(madeit && pen == 0){
points += 100;
if(combo <= 0)
combo = 1;
else
combo++;
}
switch(combo){
case 3:
combo = 0;
level++;
break;
case 2:
cout << "One more for next challenge!!!" << endl;
break;
case -2:
cout << "Make next round for not going back!!!" << endl;
break;
case -3:
combo = 0;
level--;
break;

}
cout << endl;
}
}
int main(){
srand(time(0));
start();
return 0;
}

[jonnin]

Of course.
You look like you are right there on top of it...
get the time now. save it as start time.
run the code.
get the time now again.
Difference = run time.
if the code executes so fast this is zero every time, look at other posts here and on google about high resolution timers, be sure that whatever you look at is in the last couple of years. Most timers can only measure large chunks (compared to PC clock speeds --- as Data said in trek... for an android it was an eternity ...)

if you want an average done for you (vs manually tracking in excel or something) you

for(bunch of runs)
{
get start
run
get end
get diff, add to total
}
avg = total/bunchofruns

[jonnin]

I forgot to say... if the code runs in a loop normally the above works. If it is run here and there at different times between other code, that isnt accurate because of caching and paging and other things. Basically code runs faster when you run the same code again, and slower if something is between runs, for a variety of reasons.