整数の２乗と浮動小数点数２乗 (関数マクロ)

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整数の２乗と浮動小数点数２乗 (関数マクロ)

C

#include <stdio.h>
#define sqr(x) ((x) * (x))
int sqr_int(int x)

{

    return x * x;

}

double sqr_double(double x)

{

    return x * x;

}

int main(int argc, char* argv[])

{

    int    nx = 3;

    double dx = 4.25;
    printf("%d * %d = %d\n", nx, nx, sqr_int(nx));

    printf("%d * %d = %d\n", nx, nx, sqr(nx));

    putchar('\n');
    printf("%lf * %lf = %lf\n", dx, dx, sqr_double(dx));

    printf("%lf * %lf = %lf\n", dx, dx, sqr(dx));

    putchar('\n');
    return 0;

}

実行結果

T:\>lesson060\Project1.exe

3 * 3 = 9

3 * 3 = 9
4.250000 * 4.250000 = 18.062500

4.250000 * 4.250000 = 18.062500