C语言程序设计 (何钦铭 颜晖 著) 高等教育出版社第四章 课后答案

1、练习43#include #include void main()double eps,s,item,flag,denominator;s=0;item=1;flag=1;denominator=1;printf(enter eps: );scanf(%lf,&eps);while(fabs(item)=eps)item=flag/denominator;s=s+item;flag=-flag;denominator=denominator+3;printf(s=%lfn,s);练习44#include void main()int num,n;float score,total=0;num=

2、0;n=0;printf(please input score # 1 :);scanf(%f,&score);while(score=0)if(score60)num+;total=total+score;n+; printf(please input score #%d(0100): ,n+1);scanf(%f,&score);printf(the average score is %.2f.n,total/n); printf(the numbers between 0 and 59 is %d.n,num);练习47#include void main()int i,j,n,num;

3、printf(enter n : );scanf(%d,&n);for(i=1;i=n;i+) printf(please input an integer : );scanf(%d,&num);for(j=2;jnum-1 & num!=1)printf(%d is a prime.n,num);else printf(%d is not a prime.n,num);练习48#include void main()int i,j,n;double e,product;e=1;printf(enter n : );scanf(%d,&n);for(i=1;i=n;i+)product=1;f

4、or(j=1;j=i;j+)product=product*j;e=e+1/product;printf(e=%.2lfn,e);练习411#include void main()int i,n,min,num;printf(enter n : );scanf(%d,&n);for(i=1;i=n;i+)printf(enter an integer : );scanf(%d,&num);if(i=1)min=num;else if(nummin)min=num;printf(the min number is %d.n,min);练习412#include void main()int nu

5、m1,num2=0,flag=1;printf(enter an integer : );scanf(%d,&num1);if(num10)flag=-1;num1=-num1;while(num1!=0)num2=num2*10+num1%10;num1=num1/10;num2=flag*num2;printf(the new number is %d.n,num2);练习413#include void main()int i,j,count=0;for(i=100;i=200;i+)for(j=2;ji-1)count+;if(count%8=0)printf(%8dn,i);else

6、 printf(%8d,i);printf(n);练习414#include void main()int i,f1=1,f2=1,f;printf(%8dn,f1);printf(%8dn,f2); /*输出前两项*/for(i=3;i=20;i+) f=f2;f2=f1+f2;f1=f;printf(%8dn,f2);printf(n);习题41#include void main()int num=1,sum=0;while(num0) printf(enter an integer :);scanf(%d,&num);if(num=0)break;if(num%2=0)sum=sum+

7、num;printf(the sum is %d.n,sum);习题42#include #include double fact(int n);void main()int i=1;double x,item,s=0;printf(enter x :);scanf(%lf,&x);item=x;while(fabs(item)=0.00001) s=s+item;i+;item=pow(x,i)/fact(i);printf(the sum is %lf.n,s);double fact(int n)int i;double product=1;for(i=1;i=n;i+)product=

8、product*i;return product;习题43#include void main()int num,sum=0,count=0;printf(enter an integer :);scanf(%d,&num);if(num0) sum=sum+num%10;num=num/10;count+;printf(the sum is %d.n,sum);printf(the count is %d.n,count);习题44#include void main()int i,n;double a,b,x,sum;a=2;b=1;sum=0; /*a为分子，b为分母*/printf(e

9、nter an integer : ); /*输入项数*/scanf(%d,&n);for(i=1;i=n;i+) /*求前n项之和*/sum=sum+a/b;x=a+b;b=a;a=x;printf(the sum is %lf.n,sum); /*输出和*/习题45#include void main()int i,j,a,n;double item,sum; /*item为项变量，sum为累加和变量*/sum=0;printf(enter two integers a and n : ); scanf(%d%d,&a,&n);for(i=1;i=n;i+) /*求前n项之和*/item=

10、0;for(j=1;j=i;j+) /*求第i项*/item=item*10+a;sum=sum+item;printf(the sum is %lf.n,sum); /*输出和*/习题46#include void main()int i,j,k,count; /*count为换法种数，i为1分的硬币数，j为2分的硬币数，k为5分的硬币数*/count=0;for(i=1;i=100;i+) for(j=1;j=50;j+)for(k=1;k=20;k+)if(i+2*j+5*k=100)printf(1分=%d, 2分=%d, 5分=%dn,i,j,k);count+;printf(换法种

11、数=%dn,count);习题47#include void main()int i,m,digit,sum; /*sum为各位数字的立方和变量*/for(i=1;i=10000;i+) /*求整数i中各位数字的立方和*/m=i;sum=0;while(m!=0)digit=m%10; sum=sum+digit*digit*digit;m=m/10;if(i=sum)printf(%dn,i); /*输出满足条件的整数i*/习题48#include int prime(int n);void main()int m,i; for(m=6;m=100;m=m+2) for(i=2;i=m-1;

12、i+)if(prime(i) & prime(m-i)printf(%d=%d+%dn,m,i,m-i);break;int prime(int n) /*判定n是否素数的函数，返回1表示素数，返回0表示非素数*/int i,flag;flag=1; /*初值为1*/for(i=2;i=n-1;i+)if(n%i=0)flag=0;break; /*置flag为0，表示非素数*/return flag;习题49#include void main()long int m,n,pow,digit; /*m为长整数变量，pow为m的幂*/printf(enter a long integer :)

13、; /*输入一个长整数m*/scanf(%ld,&m);/*求长整数m的幂，存放在pow变量中*/n=m;pow=1;while(n!=0)n=n/10;pow=pow*10;pow=pow/10;/*从m的最高位开始，逐位输出各数位上的数字*/while(m!=0)digit=m/pow; /*求最高位数字*/m=m%pow; pow=pow/10; /*幂pow缩小10倍*/printf(%d ,digit);printf(n);习题410#include void main()int i,m,n;printf(enter an integer m :); /*输入一个正整数m*/scan

14、f(%d,&m);n=m/2; printf(%d=1,m);for(i=2;i=n;i+)while(m%i=0)printf(*%d,i);m=m/i;printf(n);习题411#include void main(void) int m, n, j, k; /* j表示最小公倍数，k表示最大公约数 */ printf(input two integer m and n : ); scanf(%d%d,&m,&n);j = m; while(j % n != 0) /* 求最小公倍数，存放在j变量中 */j = j + m;k = (m * n) / j; /* 求最大公约数，存放在k

15、变量中 */ printf(最小公倍数是%d n最大公约数是%dn , j, k);习题412#include void main(void) int i; double h,s; /* h为高度，s为总路程 */h=100;s=100; /* 赋初值 */for(i=1;i10;i+) /* 循环9次，求出第10次落地的总路程 */h=0.5*h;s=s+2*h;h=0.5*h; /* 第10次反弹的高度 */ printf(第10次落地的总路程是%lf, 第10次反弹的高度是%lfn , s, h);习题413#include void main(void) int i,j;for(i=1;i=7;i+)if(i=4) /* 输出图形的上4行 */for(j=1;j=20-2*i;j+)printf( ); /* 输出行前的空格 */for(j=1;j=2*i-1;j+)printf(* ); /* 输出一行中的* */else /* 输出图形的下3行 */for(j=1;j=12+2*(i-4);j+)pri