abc020.contest.atcoder.jp #include <iostream> using namespace std; void Solve(int a, int b) { int number=b, digit=1; while (number > 0) { digit*=10; number/=10; } cout << (a*digit+b)*2 << endl; } int main(void) { int a, b; cin >> a >> b; Solve(a,b);</iostream>…

abc020.contest.atcoder.jp #include <iostream> #include <string> using namespace std; void Solve(int q) { string answer[2]={"ABC", "chokudai"}; cout << answer[q-1] << endl; } int main(void) { int q; cin >> q; Solve(q); return 0; } 入力の値が1ならABC、2ならch</string></iostream>…