（12） About time-consuming printing

It is used to judge the time-consuming printing of a program

#include <chrono>
int main(){
	auto start = std::chrono::steady_clock::now();
	int res=countNonZero(s,srcBase,s.width);  //do some things
	auto end = std::chrono::steady_clock::now();
	auto ms = std::chrono::duration_cast<std::chrono::milliseconds>(end-start);
	double time = ms.count();
	std::cout<<"res:"<<res<<","<<time<<std::endl;
}