1 #include <stdio.h> 2 3 //判断是否是三角形 4 void judgeTriangle(float a,float b,float c) 5 { 6 //验证边与边的关系 7 if( (a + b > c) && (a + c > b) && (b + c > a) ) 8 { 9 printf("It's a triangle!\n\n") ; 10 } 11 else 12 { 13 printf("It's not a triangle!\n\n") ; 14 } 15 } 16 17 int main(void) 18 { 19 float n1, n2, n3; 20 while(1) 21 { 22 //输入三边的值 23 printf("Please input 3 numbers : \n") ; 24 scanf("%f %f %f",&n1, &n2, &n3) ; 25 26 //判断三边是否都大于0,否则退出程序 27 if( (n1 > 0) && (n2 > 0) && (n3 > 0) ) 28 { 29 judgeTriangle(n1,n2,n3) ; 30 } 31 else break ; 32 } 33 return 0 ; 34 }