python vs cpp 表现不同

Question

这两个程序都是求两个数的公约数。

输入：a=100000 b=100000

python 36 (correct)

cpp 35 (wrong)

首先我找到两个数的gcd，然后找到gcd的因数以获得公约数。我从 here 中找到了 python 程序我试图将它转换成 cpp，但我得到了错误的答案。

python:

    def ngcd(x, y):
        i=1
        while(i<=x and i<=y):
            if(x%i==0 and y%i == 0):
                gcd=i;
            i+=1
        return gcd;
    def num_comm_div(x, y):
      n = ngcd(x, y)
      result = 0
      z = int(n**0.5)
      i = 1
      while( i <= z ):
        if(n % i == 0):
          result += 2 
          if(i == n/i):
            print("I am executed at ",i)  # never executed
            result-=1
        i+=1
      return result

    print("Number of common divisors: ",num_comm_div(2, 4))
    print("Number of common divisors: ",num_comm_div(2, 8))
    print("Number of common divisors: ",num_comm_div(100000, 100000))

cpp:

    #include<bits/stdc++.h>
    #include<cmath>
    using namespace std;
    int gcd(int a,int b){
        if(b==0)
            return a;
        return gcd(b,a%b);
    }


    int main(){
        int t;
        cin>>t;
        while(t--){
            int a,b;
            cin>>a>>b;
            int n = gcd(a,b);
            cout<<n<<endl;
            int ans=0;
            for(int i=1;i<=(int)sqrt(n);i++){
                if(n%i==0){
                    ans+=2;
                }
                if(i==n/i)
                {
                    printf("I am executed at %d  \n",i);//executed at i=316
                    ans--;
                }
            }
            cout<<ans<<endl;
        }
    }

Answer 1

在Python中注意这个if：

if(n % i == 0):
    result += 2 
    if(i == n/i):
        print("I am executed at ",i)  # never executed
        result-=1

第二个 if 包含在第一个的正文中。你在 C++ 中对应的块应该是：

if(n%i==0){
    ans+=2;

    if(i==n/i)
    {
        printf("I am executed at %d  \n",i);//executed at i=316
        ans--;
    }
}

python vs cpp 表现不同

python vs cpp behaving differently

python

c++

numbers

theory