C语言练习题答案.docx

,b,c,计算三角形面积的公式为:area=sqrt(s(s-a)(s-b)(s-c)),其中s=(a+b+c)/2。试编程从键盘输入a,b,c的值(假设a,b,c的值可以保证其构成一个三角形),计算并输出三角形的面积。**输入格式要求:"%f,%f,%f"提示信息:"Inputa,b,c:"**输出格式要求:"area=%.2f\n"程序运行示例如下:Inputa,b,c:3,4,5area=:#include<>#include<>intmain(void){ floata,b,c,s,area; printf("Inputa,b,c:"); scanf("%f,%f,%f",&a,&b,&c); s=(a+b+c)/2; area=sqrt(s*(s-a)*(s-b)*(s-c)); printf("area=%.2f\n",area); return0;}-----------------,:输入1234,分离出千位1、百位2、十位3和个位4,然后计算4*1000+3*100+2*10+1=4321,并输出4321。**要求输入提示信息为:无**要求输入格式为:"%d"**要求输出格式为:"%d"程序运行示例如下:1234此处为输入4321此处为输出答案:#include<>intmain(void){ inta,b,c,d,e; scanf("%d",&a); b=a/1000; c=a%1000/100; d=a%100/10; e=a%10; a=e*1000+d*100+c*10+b; printf("%d",a); return0; }--------------。输入为:12a↙b↙运行结果为:1,2,a,b,,65535请改正程序中的错误,使它能得出正确的结果。#include<>main(){intb;unsignedshorta=65535;shortk=a;charc,d;intf,g;b=(-1)/10;scanf("%c",&c);scanf("%c",&d);scanf("%d",&f);scanf("%d",&g);printf("%c,%c,%c,%c,%f,%d",c,d,f,g,b,k);}答案:#include<>main(){doubleb;inta=65535;charc,d;intf,g;b=(-1)/10;scanf("%c",&c);scanf("%c",&d);scanf("%c\t",&f);scanf("%c",&g);printf("%c,%c,%c,%c,%f,%d",c,d,f,g,b,a);}--------,统计其中的英文字符、数字字符、空格字符,以及其他字符的个数。请找出以下程序的错误,并改正之。#include<>#include<> #defineARR_SIZE=80;  main(){    charstr[ARR_SIZE];    int len,i;    int letter=0,digit=0,space=0,other=0;     printf("请输入一个字符串:");    gets(str);     len=strlen(str);        for(i=0;i<len;i++)    {        if(a=<str[i]<=z||A=<str[i]<=Z)        {            letter++;          }                       elseif(0=<str[i]<=9)        {            digit++;             }                   elseif(str[i]='')          {                              space++;            }               else            other++;                }     printf("英文字符数:%d\n",letter);    printf("数字字符数:%d\n",digit);    printf("空格数:%d\n",space);    printf("其他字符数:%d\n",other);}答案:#include<>#include<string.