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Why does scanf require &?（7个回答）
24天前关闭

#include <stdio.h>

int main(){

    double Radius, Circumference, Area, Pi = 3.1416;
    
    printf("Value of Radius:");
    scanf("%lf",Radius);
    
    Area = Pi * Radius * Radius;
    Circumference = 2 * Pi * Radius;
    
    printf("The area of the circle is %lf", Area);
    printf("\nThe circumference of the circle is %lf", Circumference);
    
    return 0; 
}

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