# include <stdio.h># include <math.h> /*此头文件为调用 sqrt() 求平方根而用*/int main(void){ int a; int b; int c; double x1; double x2; double delta; //定义 delta = b*b = 4*a*c /*请用户输入三个整数 a b c, 并分别以空格键为间隔*/ printf("请分别输入一元二次方程 a b c 的三个数值,请以空格为间隔:\n"); scanf("%d %d %d", &a, &b, &c); delta = b*b - 4*a*c; if (delta > 0) { x1 = (-b + sqrt(delta)) / (2*a); x2 = (-b - sqrt(delta)) / (2*a); printf("该一元二次方程有两个解: x1 = %lf, x2 = %lf\n", x1, x2); } else if (delta == 0) { x1 = (-b) / (2*a); x2 = x1; printf("该一元二次方程有一个解: x1 = x2 = %lf\n", x1); } else { printf("无解\n"); } return 0;}