第二章作业

2.1 #include <iostream> using namespace std; int main() { int n; cin >> n; if(n>=90) cout << "A"; else if(n>=80) cout << "B"; else if(n>=70) cout << "C"; else if(n>=60) cout << "D"; else cout << "E"; return 0; } 2.2： #include <iostream> using namespace std; int main(){ int a,b,sum,difference,product,quotient,remainder; cin>>a>>b; sum = a + b; difference = a - b; product = a * b; quotient = a / b; remainder = a % b ; cout<<"sum="<<sum<<endl<<"difference="<<difference<<endl<<"product="<<product<<endl<<"quotient="<<quotient<</endl<"remainder="<remainder<</endl ; return 0;}