题解 | #简单计算器#

#include <stdio.h>

int main() {
    double n1 = 0.0;
    double n2 = 0.0;
    char op = 0;
    while (~scanf("%lf%c%lf", &n1, &op, &n2)) {
        switch (op) {
            case'+':
                printf("%.4lf+%.4lf=%.4lf\n", n1, n2, n1 + n2);
                break;
            case'-':
                printf("%.4lf-%.4lf=%.4lf\n", n1, n2, n1 - n2);
                break;
            case'*':
                printf("%.4lf*%.4lf=%.4lf\n", n1, n2, n1 * n2);
                break;
            case'/':
                if (0.0 == n2) {
                    printf("Wrong!Division by zero!\n");
                } else {
                    printf("%.4lf/%.4lf=%.4lf\n", n1, n2, n1 / n2);
                }
                break;
            default:
                printf("Invalid operation!\n");
                break;
        }
    }
    return 0;
}