今天因为好奇扒取了 leetcode 服务器端的开发环境。

---

• 方法：随便找个题，利用stdout 输出系统信息，如下：

  

• 完整信息如下：

  === os information ===
  Linux version 4.4.0-131-generic (buildd@lgw01-amd64-015) (gcc version 5.4.0 20160609 (Ubuntu 5.4.0-6ubuntu1~16.04.10) ) #157-Ubuntu SMP Thu Jul 12 15:51:36 UTC 2018
  === cpu infomation ===
  processor : 0
  vendor_id : GenuineIntel
  cpu family : 6
  model : 79
  model name : Intel(R) Xeon(R) CPU E5-2697A v4 @ 2.60GHz
  stepping : 1
  microcode : 0x1
  cpu MHz : 2599.996
  cache size : 40960 KB
  physical id : 0
  siblings : 1
  core id : 0
  cpu cores : 1
  apicid : 0
  initial apicid : 0
  fpu : yes
  fpu_exception : yes
  cpuid level : 13
  wp : yes
  flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon rep_good nopl eagerfpu pni pclmulqdq vmx ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm 3dnowprefetch invpcid_single kaiser tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm rdseed adx smap xsaveopt
  bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass
  bogomips : 5199.99
  clflush size : 64
  cache_alignment : 64
  address sizes : 40 bits physical, 48 bits virtual
  power management:
  processor : 1
  vendor_id : GenuineIntel
  cpu family : 6
  model : 79
  model name : Intel(R) Xeon(R) CPU E5-2697A v4 @ 2.60GHz
  stepping : 1
  microcode : 0x1
  cpu MHz : 2599.996
  cache size : 40960 KB
  physical id : 1
  siblings : 1
  core id : 0
  cpu cores : 1
  apicid : 1
  initial apicid : 1
  fpu : yes
  fpu_exception : yes
  cpuid level : 13
  wp : yes
  flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon rep_good nopl eagerfpu pni pclmulqdq vmx ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm 3dnowprefetch invpcid_single kaiser tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm rdseed adx smap xsaveopt
  bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass
  bogomips : 5199.99
  clflush size : 64
  cache_alignment : 64
  address sizes : 40 bits physical, 48 bits virtual
  power management:
  === memory information ===
  MemTotal: 4046404 kB
  MemFree: 1329068 kB
  MemAvailable: 1974100 kB
  Buffers: 159648 kB
  Cached: 597080 kB
  SwapCached: 29884 kB
  Active: 1286924 kB
  Inactive: 602876 kB
  Active(anon): 657084 kB
  Inactive(anon): 515256 kB
  Active(file): 629840 kB
  Inactive(file): 87620 kB
  Unevictable: 3652 kB
  Mlocked: 3652 kB
  SwapTotal: 524284 kB
  SwapFree: 3020 kB
  Dirty: 12 kB
  Writeback: 0 kB
  AnonPages: 1107024 kB
  Mapped: 44892 kB
  Shmem: 36728 kB
  Slab: 720068 kB
  SReclaimable: 215152 kB
  SUnreclaim: 504916 kB
  KernelStack: 4848 kB
  PageTables: 9472 kB
  NFS_Unstable: 0 kB
  Bounce: 0 kB
  WritebackTmp: 0 kB
  CommitLimit: 2547484 kB
  Committed_AS: 2099816 kB
  VmallocTotal: 34359738367 kB
  VmallocUsed: 0 kB
  VmallocChunk: 0 kB
  HardwareCorrupted: 0 kB
  AnonHugePages: 0 kB
  CmaTotal: 0 kB
  CmaFree: 0 kB
  HugePages_Total: 0
  HugePages_Free: 0
  HugePages_Rsvd: 0
  HugePages_Surp: 0
  Hugepagesize: 2048 kB
  DirectMap4k: 3686380 kB
  DirectMap2M: 507904 kB
  DirectMap1G: 0 kB

• 源代码（获取系统信息的代码)：

#include 
    
     #include 
     
      #include 
      
        // mostly need to read the linux config files to get system info // ---- get os info ---- //void getOsInfo(){    FILE *fp = fopen("/proc/version", "r");    if(NULL == fp)        printf("failed to open version\n");    char szTest[1000] = {0};    while(!feof(fp))    {        memset(szTest, 0, sizeof(szTest));        fgets(szTest, sizeof(szTest) - 1, fp); // leave out \n        printf("%s", szTest);    }    fclose(fp);}// ---- get cpu info ---- //void getCpuInfo(){    FILE *fp = fopen("/proc/cpuinfo", "r");    if(NULL == fp)        printf("failed to open cpuinfo\n");    char szTest[1000] = {0};    // read file line by line    while(!feof(fp))    {        memset(szTest, 0, sizeof(szTest));        fgets(szTest, sizeof(szTest) - 1, fp); // leave out \n        printf("%s", szTest);    }    fclose(fp);}  // ---- get memory info ---- //void getMemoryInfo(){    FILE *fp = fopen("/proc/meminfo", "r");    if(NULL == fp)        printf("failed to open meminfo\n");    char szTest[1000] = {0};    while(!feof(fp))    {        memset(szTest, 0, sizeof(szTest));        fgets(szTest, sizeof(szTest) - 1, fp);        printf("%s", szTest);    }    fclose(fp);} // ---- get harddisk info ---- //#include 
       
        #include 
        
         #include 
         
           void lin(){ printf("=== os information ===\n"); getOsInfo(); printf("=== cpu infomation ===\n"); getCpuInfo(); printf("=== memory information ===\n"); getMemoryInfo();}class Solution {public: vector
          
           
            > threeSum(vector
            
             & nums) { lin();//选哪个题无所谓，调用一遍lin()就行，此处是选的3Sum这题 vector
             
              
               > t; return t; }};