#include <stdio.h> #define PI 3.1415926 int main() { int n; printf("请输入圆的数量："); scanf("%d", &n); for (int i = 0; i < n; ++i) { int radius; printf("请输入第%d个圆的半径：", i+1); scanf("%d", &radius); double area = PI * radius * radius; printf("面积：%.6f\n", area); } return 0; }