/* Goldbach's Conjecture Goldbach's conjecture is a rule in math that states the following: every even number greater than 2 can be expressed as the sum of two prime numbers. Write a program that finds every possible pair of prime numbers, whose sum equals the given number or a set of numbers within a range. For example: Input: 16 Output: 3 + 13 5 + 11 Input: 32 Output: 3 + 29 13 + 19 Input: 4 8 Output: 4: 2 + 2 6: 3 + 3 8: 3 + 5 */ #include #include #include #include #include #include auto prime = [](int n)->int{ if(n==2 || n==3) return 1; if(n<2) return 0; for(int i(2);i<=(int)sqrt(n);i++){ if(!(n%i)) return 0; } return 1; };//lambda function int range(std::string s){ for(char c : s){//for char c in s if((int)c==32)//(char)32=' ' return 1; } return 0; } std::vector get_range(std::string s){ std::vector v; int l(s.length()); for(int i(0);i!=l;i++){ int c=(int)s.at(i); if(c==32){ v.insert(v.end(), {stoi(s.substr(0,i)),stoi(s.substr(i+1))}); } } return v; } std::string goldbach(int n,int range=0){ if(n<=1) throw 42; std::stringstream sr; std::vector base; for(int i(2);i!=n+1;i++){ if(prime(i)) base.push_back(i); } int l(base.size()),i(0); while(i r=get_range(s); int debut=r[0],fin=r[1]; for(;debut!=fin+1;debut++){ if(!(debut%2)) std::cout< header... } }

goldbach.cpp