C語言編寫的，可以參考。

#include<stdio.h>

#include<math.h>

void judge(float a,float b,float c)

{

float p;

if((((a+b)>c)&&(fabs(a-b)<c))||

(((b+c)>a)&&(fabs(b-c)<a))||

(((a+c)>b)&&(fabs(a-c)<b)))

{

printf("San jiao xing de bian chang shi : %f,%f,%f\n",a,b,c);

printf("San jiao xing de zhou chang shi : %f\n",a+b+c);

p=(a+b+c)/2;

printf("San jiao xing de mian ji shi : %f\n",sqrt(p*(p-a)*(p-b)*(p-c)));

}

else

{

printf("Error\n");

}

}

main()

{

float a,b,c;

int flag=0;

printf("Which do you wnat ?\n1 Creat a triangle.\n0 Exit\n");

scanf("%d",&flag);

while(flag==1)

{

printf("Please enter three bain chang :\n");

scanf("%f",&a);

scanf("%f",&b);

scanf("%f",&c);

judge(a,b,c);

printf("Which do you wnat ?\n1 Creat a triangle.\n2 Exit\n");

scanf("%d",&flag);

}

}