C++ 等差/等比数列判断与计算 - 猜猜下一个数

#include #include using namespace std;

int main() { int N; cin >> N;

vector<int> A(N);
for (int i = 0; i < N; i++) {
    cin >> A[i];
}

int diff = A[1] - A[0];
int ratio = A[1] / A[0];
bool isArithmetic = true;
bool isGeometric = true;

for (int i = 2; i < N; i++) {
    if (A[i] - A[i-1] != diff) {
        isArithmetic = false;
    }
    if (A[i] / A[i-1] != ratio) {
        isGeometric = false;
    }
}

int AN;
if (isArithmetic) {
    AN = A[N-1] + diff;
} else if (isGeometric) {
    AN = A[N-1] * ratio;
}

cout << AN << endl;

return 0;

}