C语言上机练习题

1、1.输入一个不超过五位的正整数，输出其逆数。例如输入12345，输出应为54321。#include"stdio.h"main()longn;intww,qw,bw,sw,gw;printf("Pleaseinput:n");scanf("%ld",&n);while(n<=0|n>99999)printf("nThenumberistoolittleortoolarge.Retryplease!n");scanf("%ld",&n);if(n>=10000&a

2、mp;&n<=99999)ww=n/10000;qw=n/1000%10;bw=n/100%10;sw=n/10%10;gw=n%10;printf("Theoldnumberis:%ldn",n);printf("Thenewnumberis:%d%d%d%d%dn",gw,sw,bw,qw,ww);elseif(n>=1000&&n<=9999)qw=n/1000;bw=n/100%10;sw=n/10%10;gw=n%10;printf("Theoldnumberis:%ldn",n);

3、printf("Thenewnumberis:%d%d%d%dn",gw,sw,bw,qw);elseif(n>=100&&n<=999)bw=n/100;sw=n/10%10;gw=n%10;printf("Theoldnumberis:%ldn",n);printf("Thenewnumberis:%d%d%dn",gw,sw,bw);elseif(n>=10&&n<=99)sw=n/10;gw=n%10;printf("Theoldnumberis:%ldn&qu

4、ot;,n);printf("Thenewnumberis:%d%dn",gw,sw);elseprintf("Theoldnumberequalsthenewnumber:%ld",n);2. 计算1+2+3+n的值，n是从键盘输入的自然数。/*Note:YourchoiceisCIDE*/#include"stdio.h"main()intn,i;longsum=0;printf("1+2+3+nn");printf("Pleaseinputn:n");scanf("%d"

5、;,&n);for(i=1;i<=n;i+)sum+=i;printf("sum=%ld",sum);3. 从终端(键盘)读入20个数据到数组中，统计其中正数的个数，并计算这些正数之和。、/*Note:YourchoiceisCIDE*/#include"stdio.h"#defineN20main()intaN,i,sum=0,count=0;printf("Pleaseinputnumbers:n");for(i=0;i<N;i+)scanf("%d",&ai);if(ai>0

6、)sum+=ai;count+;printf("count=%d,sum=%d",count,sum);4. 从终端(键盘)将5个整数输入到数组a中，然后将a逆序复制到数组b中，并输出b中各元素的值。/*Note:YourchoiceisCIDE*/#include"stdio.h"#defineN5main()intaN,bN,i;printf("Pleaseinputnumbers:n");for(i=0;i<N;i+)scanf("%d",&ai);bN-i-1=ai;printf("

7、nTheoldnumbersare:n");for(i=0;i<N;i+)printf("%-4d",ai);printf("nThenewnumbersare:n");for(i=0;i<N;i+)printf("%-4d",bi);5. 要将五张100元的大钞票，换成等值的50元，20元，10元，5元一张的小钞票，每种面值至少1 张，编程输出所有可能的换法，程序应适当考虑减少重复次数。/*Note:YourchoiceisCIDE*/#include"stdio.h"main()inti,

8、j,k,n;for(i=1;i<=10;i+)for(j=1;j<=25;j+)for(k=1;k<=50;k+)for(n=1;n<=100;n+)if(i*50+j*20+k*10+n*5=500)printf("num50=%d,num20=%d,num10=%d,num5=%dn",i,j,k,n);6.求n以内(不包括n)同时能被3和7整除的所有自然数之和的平方根s，n从键盘输入。例如若n为1000时，函数值应为：s=153.909064。/*Note:YourchoiceisCIDE*/#include"stdio.h"

9、;#include"math.h"main()intn,s,i;floatsum=0;printf("Pleaseinputn:n");scanf("%d",&n);while(n<=0)printf("nErrorinput.Retryplease:n");scanf("%d",&n);for(i=1;i<n;i+)if(i%3=0&&i%7=0)sum+=i;printf("Thenumberis:%4.2f",sqrt(sum

10、);7.一辆卡车违反交通规则，撞人后逃跑。现场有三人目击事件，但都没有记住车号，只记下车号的一些特征。甲说：牌照的前两位数字是相同的；乙说：牌照的后两位数字是相同的，但与前两位不同；丙是数学家，他说：四位的车号刚好是一个整数的平方。请根据以上线索找出车号。/*Note:YourchoiceisCIDE*/#include"stdio.h"#include"math.h"main()inti,qw,bw,sw,gw;for(i=1122;i<=9988;i+)if(sqrt(i)!=(int)sqrt(i)continue;qw=i/1000;bw=

11、i/100%10;sw=i/10%10;gw=i%10;if(qw=bw&&sw=gw)printf("nThenumberis:%dn",i);break;8. 输入110之间的一个数字，输出它对应的英文单词。/*Note:YourchoiceisCIDE*/#include"stdio.h"main()intn;printf("Pleaseinputn:n");scanf("%d",&n);while(n<1|n>10)printf("Errorinput!Retr

12、yplease:n");scanf("%d",&n);switch(n)case1:printf("One!");break;case2:printf("Two!");break;case3:printf("Three!");break;case4:printf("Four!");break;case5:printf("Five!");break;case6:printf("Six!");break;case7:printf("

13、Seven!");break;case8:printf("Eight!");break;case9:printf("Nine!");break;case10:printf("Ten!");break;9. 个位数为6且能被3整除但不能被5整除的三位自然数共有多少个，分别是哪些？/*Note:YourchoiceisCIDE*/#include"stdio.h"main()inti,count=0;for(i=106;i<596;i=i+10)if(i%3=0&&i%5!=0)prin

14、tf("%-4d",i);count+;printf("count=%-4d",count);10. 用自然语言描述程序逻辑如下，试写程序。 设置环境； 定义变量i、j、s，以及用于放置结果的变量sum并令sum初值为0； i=1；如果i<100,则转，否则转； 令s=0，求前i个自然数之和，并放于变量s之中； sum=sum+s； i增加1，转；输出和sum,结束。/*Note:YourchoiceisCIDE*/#include"stdio.h"main()inti,j;longs=0,sum=0;printf("

15、1+1+2+1+2+3+1+2+3+4+1+2+3+.+nn");i=1;while(i<=3)s+=i;sum+=s;i+;printf("sum=%ld",sum);11. 用自然语言描述的程序逻辑为： 设置环境； 定义变量i、flag和password，并令flag=0，i=0； 用户回答口令，将其赋于password变量； 口令正确？如果是，则flag=1,转。否则转； 回答三次口令了吗？如果没有，计数器加1后(i+)，转，否则转； 根据flag之值输出相应信息。/*Note:YourchoiceisCIDE /#include"stdio

16、.h"#include"string.h" defineN6main()inti=0,flag=0;charpasswordN;printf("Thepasswordis:123456n");while(i<3)gets(password);if(strlen(password)!=6)printf("Thestringlengthiswrong!Retryplease!n");i+;continue;if(strcmp("123456",password)=0)flag=1;break;elsep

17、rintf("Wronginput!Retryplease!n");i+;if(flag=1)printf("Rightpassword!n");elseprintf("Wrongpassword!n");12. 用自然语言描述的程序逻辑如下： 设置环境； 定义变量digit、x、y分别表示原始数、原始数的个位数和逆 输入原始正整数x； 从x中分解出个位数字digit； 合并个位digit至逆数y中； 原始数x缩小10倍：x=x/10；如果x非零，则转； 输出逆数y，结束/*Note:YourchoiceisCIDE*/#includ

18、e"stdio.h"main()longdigit,x,y;/*个位数、原始数、逆数*/printf("Pleaseinputtheoldnumber:n");scanf("%ld",&x);digit=x%10;y=digit;while(x!=0)x=x/10;digit=x%10;y=y*10+digit;printf("x=%ld,y=%ld",x,y/10);13. 输入某三角形的三个边的长度，判断出这是个什么三角形(等腰、等边、任意，或不能构成)。/*Note:YourchoiceisCIDE*

19、/#include"stdio.h"main()floata,b,c,flag;/*flag=0不能，flag=1等边,flag=2等腰，flag=3任意*/printf("Pleaseinputangles:n");scanf("%f,%f,%f",&a,&b,&c);if(a+b<=c|a+c<=b|b+c<=a)flag=0;elseif(a=b&&b=c)flag=1;elseflag=2;if(a=b|b=c|c=a)elseflag=3;if(flag=0)prin

20、tf("nCannot!n");if(flag=1)printf("nDengBian.n");if(flag=2)printf("nDengYao.n");if(flag=3)printf("nPutong.n");14. 输入10个数，分别统计其中正数、负数、零的个数。#include"stdio.h"#defineN10main()intaN;inti,count1=0,count2=0,count3=0;/*count1记录正数个数，count2记录负数个数，count3记录0的个数*/

21、printf("Pleaseinputnumbers:n");for(i=0;i<N;i+)scanf("%d",&ai);if(ai>0)count1+;if(ai<0)count2+;if(ai=0)count3+;printf("count1=%-4d,count2=%-4d,count3=%-4d",count1,count2,count3);15. 先随机产生N个三位自然数输出，然后再输出其中同时是3、5、7倍数的数。(设N为100)/*Note:YourchoiceisCIDE*/#include

22、"stdio.h"#defineN100#include<time.h>#include<stdlib.h>main()intaN,i;printf("Pleaseinputnumbers:n");randomize();for(i=0;i<N;i+)ai=random(900)+100;printf("%-4d",ai);n");printf("n3,5,7:n");for(i=0;i<N;i+)if(ai%3=0&&ai%5=0&&a

23、i%7=0)printf("%-4d",ai);16. 用for编程找出100200中的完全平方数。#include"stdio.h"#include"math.h"main()inti;for(i=100;i<=200;i+)if(sqrt(i)=i%100)printf("%-4d",i);17. 从终端输入三个正实数，判断这三个数能否构成直角三角形。#include"stdio.h"main()floata,b,c,flag;/*flag=0不能，flag=1能*/printf(&q

24、uot;Pleaseinputangles:n");scanf("%f,%f,%f",&a,&b,&c);while(a<=0|b<=0|c<=0)printf("Wronginput!Retryplease:n");scanf("%d,%d,%d",&a,&b,&c);if(a+b<=c|b+c<=a|a+c<=b)flag=0;elseif(a*a=b*b+c*c|b*b=a*a+c*c|c*c=a*a+b*b)flag=1;elsefl

25、ag=0;if(flag=1)printf("nCan!");elseprintf("nCannot!");18. 输入一行字符，统计其中有多少个字母(包括大写字母和小写字母)。/*Note:YourchoiceisCIDE*/#include"stdio.h"#defineN10#include"stdlib.h"#include"ctype.h"#include"string.h"main()charcN;inti,count=0;gets(c);i=0;while(i!

26、=strlen(c)if(isupper(ci)|islower(ci)count+;i+;printf("count=%-4d",count);getch();19. 输入一个字串，判断它是否是对称串。如”abcdcba”是对称串，123456789”不是。/*Note:YourchoiceisCIDE*/#include"stdio.h"#include"string.h"#include"ctype.h"#include"stdlib.h"#defineN10main()charaN,bN

27、,i;printf("Pleaseinputthestring:n");gets(a);if(strlen(a)>N)printf("Wronginput!Retryplease!n");gets(a);strcpy(b,a);strrev(a);if(strcmp(a,b)=0)printf("nYes!n");elseprintf("nNo!n");20. 随机产生N个大写字母输出，然后统计其中共有多少个元音字符。(设N为200)/*Note:YourchoiceisCIDE*/#include"

28、;stdio.h"#include<stdlib.h>#include<time.h>#defineN200main()intcN,i,count=0;randomize();for(i=0;i<N;i+)ci=random(27)+65;printf("%c",ci);if(ci='A'|ci='E'|ci='I'|ci='O'|ci='U')count+;printf("nn");printf("ncount=%-4d&q

29、uot;,count);找出三位自然数中的所有素数，要求判断x素数用自定义函数data(x)实现。#include"stdio.h"intdata(intx);main()inti,flag=0;/*1是，0否*/for(i=101;i<=999;i+)flag=data(i);if(flag=1)printf("%-4d",i);intdata(intx)inti;for(i=2;i<x/2;i+)if(x%i=0)return0;if(i=x/2)return1;elsereturn0;21. 输出n行由“#”组成的矩形，每行“#&quo

30、t;的个数为m个，其中n、m由终端(键盘)输入。要求输出m个“#”功能由函数satr(m)函数实现。#include"stdio.h"voidsatr(intm);main()inti,n,m;printf("Pleaseinputn&m:n");printf("n=");scanf("%d",&n);printf("m=");scanf("%d",&m);printf("nn");for(i=1;i<=n;i+)satr(m

31、);printf("n");voidsatr(intm)inti;for(i=1;i<=m;i+)printf("#");22. 若ax2+bx+c=0有实根，则求之。#include"stdio.h"#include"math.h"main()inta,b,c;floatderta,x1,x2;printf("Pleaseinputa,b,c:n");printf("a=");scanf("%d",&a);printf("b=&q

32、uot;);scanf("%d",&b);printf("c=");scanf("%d",&c);derta=b*b-4*a*c;if(derta<0)printf("NO!n");if(derta=0)printf("One!n");x1=-b/(2*a);x2=x1;printf("x=%-4.2f",x1);if(derta>0)printf("Two!n");x1=(-b+sqrt(derta)/(2*a);x2=(-b

33、-sqrt(derta)/(2*a);printf("x1=%-4.2f,x2=%-4.2f",x1,x2);23. 从键盘输入两个字串，判断它们是否相同。#include"stdio.h"#include"string.h"#defineN20main()charc1N,c2N;printf("Pleaseinputtwostringbelow:n");gets(c1);gets(c2);printf("-n");printf("Theansweris:");if(strc

34、mp(c1,c2)=0)printf("Equal!n");elseprintf("Notequal!n");24. 从键盘输入两个字串，输出其中较短的那个字串，并输出它的长度。#defineN20#include"stdio.h"#include"string.h"main()charc1N,c2N;printf("Pleaseinputtwostringbelow:n");gets(c1);gets(c2);printf("-n");printf("Theans

35、weris:");if(strlen(c1)=strlen(c2)puts(c1);puts(c2);printf("Thelengthis:%dn",strlen(c1);if(strlen(c1)<strlen(c2)puts(c1);printf("Thelengthis:%dn",strlen(c1);if(strlen(c1)>strlen(c2)puts(c2);printf("Thelengthis:%dn",strlen(c2);25.从键盘输入长度不等的两个字串，将短串连接于长串之后输出。#in

36、clude"stdio.h"#include"string.h"#defineN20main()charc1N,c2N;printf("Pleaseinputtwostringbelow:n");gets(c1);gets(c2);while(strlen(c1)=strlen(c2)printf("Wronginput!Retryplease:n");gets(c1);gets(c2);printf("n");printf("Theansweris:");if(strlen

37、(c1)<strlen(c2)puts(strcat(c2,c1);if(strlen(c1)>strlen(c2)puts(strcat(c1,c2);26. 从键盘输入长度不等的两个字串，将长串连接于短串之后输出#include"stdio.h"#include"string.h"#defineN20main()charc1N,c2N;printf("Pleaseinputtwostringbelow:n");gets(c1);gets(c2);while(strlen(c1)=strlen(c2)printf(&qu

38、ot;Wronginput!Retryplease:n");gets(c1);gets(c2);printf("-n");printf("Theansweris:");if(strlen(c1)<strlen(c2)puts(strcat(c1,c2);if(strlen(c1)>strlen(c2)puts(strcat(c2,c1);27. 随机产生N个两位自然数，降序排列后输出。(设N为20)#include"stdio.h"#include"stdlib.h"#include"

39、;time.h"#defineN20main()intaN,i,j,temp;randomize();for(i=0;i<N;i+)ai=random(900)+100;for(i=0;i<N-1;i+)for(j=i+1;j<N;j+)if(aj>ai)temp=ai;ai=aj;aj=temp;for(i=0;i<N;i+)printf("%-4d",ai);28. 从键盘输入两个字串，输出其中较长的那个字串，并输出它的长度。#defineN20#include"stdio.h"#include"st

40、ring.h"main()charc1N,c2N;printf("Pleaseinputtwostringbelow:n");gets(c1);gets(c2);printf("-n");printf("Theansweris:");if(strlen(c1)=strlen(c2)puts(c1);puts(c2);printf("Thelengthis:%dn",strlen(c1);if(strlen(c2)<strlen(c1)puts(c1);printf("Thelengthis

41、:%dn",strlen(c1);if(strlen(c2)>strlen(c1)puts(c2);printf("Thelengthis:%dn",strlen(c2);29. 从键盘输入10个战士的身高，输出平均身高，并找出哪些身高低于平均身高。#include"stdio.h"#defineN11main()floataN,sum=0;inti;printf("Pleaseinputheigths:n");for(i=0;i<N-1;i+)scanf("%f",&ai);sum+

42、=ai;aN-1=sum/(N-1);printf("Theaverageis:%-6.2fn",aN-1);");printf("Theanswerare:n");for(i=0;i<N-1;i+)if(ai<aN-1)printf("%-8.2f",ai);30. 从键盘输入10个战士的身高，输出平均身高，并找出哪些身高高于平均身高。#include"stdio.h"#defineN11main()floataN,sum=0;inti;printf("Pleaseinputhei

43、gths:n");for(i=0;i<N-1;i+)scanf("%f",&ai);sum+=ai;aN-1=sum/(N-1);printf("Theaverageis:%-6.2fn",aN-1);printf("n");printf("Theanswerare:n");for(i=0;i<N-1;i+)if(ai>aN-1)printf("%-8.2f",ai);31. 从键盘输入10个战士的身高，输出最高、最低的身高#include"stdi

44、o.h"#defineN10main()floataN,min=99999,max=-99999;inti;printf("Pleaseinputheigths:n");for(i=0;i<N;i+)scanf("%f",&ai);printf("nprintf(nfor(i=0;i<N;i+) if(ai>max)");max=ai;if(ai<min)min=ai;printf("max=%-6.2f,min=%-6.2f",max,min);。32. “百钱百鸡”问题

45、。百钱买百鸡，鸡翁一值钱三，鸡母一值钱二，鸡雏三值钱一，问鸡翁、鸡母、鸡雏各几何？#include"stdio.h"main()intjw,jm,jc;/*公鸡最多100/3=33只，母鸡最多100/2=50只,小鸡最多300只*/for(jw=1;jw<=33;jw+)for(jm=1;jm<=50;jm+)for(jc=1;jc<=300;jc+)if(jw*3+jm*2+jc/3=100&&jw+jm+jc=100)printf("JW=%d,JM=%d,JC=%dn",jw,jm,jc);33. 有三个小孩，一个比一个大2岁，已知其年龄之和为39，问这三个小孩各几岁？#include"stdio.h"main()inta,b,c;for(a=1;a<=20;a+)for(b=1;b<=20;b+)for(c=1;c<=20;c+)if(a+2=b&&b+2=c&am