C 语言必背的经典程序设计题目-选择、循环-答案选择构造必背经典程序（参照答案）1、 输入3个整数，排序后输出。#includevoidmain()intx,y,z,t;scanf("%d%d%d",&x,&y,&z);if(x>y){t=x;x=y;y=t;}/*互换 x,y 的值*/if(x>z){t=z;z=x;x=t;}/*互换 x,z 的值*/if(y>z){t=y;y=z;z=t;}/*互换 z,y 的值*/printf("smalltobig:%d%d%d\n",x,y,z);2、 求解一元二次方程ax2+bx+c=0。#include#includevoidmain()doublea,b,c,deta,x1,x2;printf("Entera,b,c:");scanf("%lf%lf%lf",&a,&b,&c);if(fabs(a)>1e-6)deta=b*b-4*a*c;if(deta>0)x1=-b/(2*a)+sqrt(deta)/(2*a);x2=-b/(2*a)-sqrt(deta)/(2*a);;printf("有两个不一样的实根：x1=%.2f,x2=%.2f\n",x1,x2);elseif(deta==0)x1=x2=-b/(2*a);printf(" 有 两 个 相 似 的 根 ： x1=x2=%.2f\n",x1);elsex1=-b/(2*a);x2=sqrt(-deta)/(2*a);printf("有两个虚根:x1=%.2f+%.2f*i，x2=%.2f-%.2f*i\n",x1,x2,x1,x2);elseprintf("二次项系数为 0，不是一元二次方程!");3、已知银行整存整取存款不一样期限的月息利率分别为：0.315% 期限一年0.330% 期限二年0.345% 期限三年0.375% 期限五年0.420% 期限八年规定输入存钱的本金和期限，求到期时能从银行得到的利息与本金的合计。#includevoidmain()doublecapital,total,interest;intdeadline;printf("Enteracapitalanddeadline:");scanf("%lf%d",&capital,&deadline);if(deadline>=8)interest=0.00420*capital*12*deadline;total=capital+interest;printf("Interest:%.3f,Total:%.3f\n",interest,total);elseif(deadline>=5&&deadline<8)interest=0.00375*capital*12*deadline;total=capital+interest;printf("Interest:%.3f,Total:%.3f\n",interest,total);elseif(deadline>=3&&deadline<5)interest=0.00345*capital*12*deadline;total=capital+interest;printf("Interest:%.3f,Total:%.3f\n",interest,total);elseif(deadline==2)interest=0.00330*capital*12*deadline;total=capital+interest;printf("Interest:%.3f,Total:%.3f\n",interest,total);elseif(deadline==1)interest=0.00315*capital*12*deadline;total=capital+interest;printf("Interest:%.3f,Total:%.3f\n",interest,total);elseprintf("scoreinputerror!\n");4、给一种不多于5位的正整数，规定：①求出它是几位数；②分别打印出每一位数字；③按逆...
