a.cpp~

#include<stdio.h>
#include<google/profiler.h>
#include<stdlib.h>
#include<unistd.h>
void consumeSomeCPUTime1(int input){ 
  int i = 0; 
  input++; 
  while(i++ < 10000){ 
    i--;  i++;  i--;  i++; 
  } 
 }; 

 void consumeSomeCPUTime2(int input){ 
  input++; 
  consumeSomeCPUTime1(input); 
  int i = 0; 
  while(i++ < 10000){ 
    i--;  i++;  i--;  i++; 
  } 
 }; 

 int stupidComputing(int a, int b){ 
  int i = 0; 
  while( i++ < 10000){  
    consumeSomeCPUTime1(i); 
  } 
  int j = 0; 
  while(j++ < 5000){ 
    consumeSomeCPUTime2(j); 
  } 
  return a+b; 
 }; 

 int smartComputing(int a, int b){ 
  return a+b; 
 }; 

 int main(){ 
  int i = 0;
  printf("reached the start point of performance bottle neck\n"); 
  sleep(5);
ProfilerStart("CPUProfile");
  while( i++ < 10){ 
    printf("Stupid computing return : %d\n",stupidComputing(i, i+1)); 
    printf("Smart computing return %d\n",smartComputing(i+1, i+2)); 
  }
  printf("should teminate profiling now.\n");  
  sleep(5);
ProfilerStop();
 }