C语言基础编程练习

1、1.屏幕上输入：This is a C program#include <stdio.h>int main()printf("This is a C program.n");return 0;2、求两个整数之和#include <stdio.h>void main()int a,b,sum;a=123;b=456;sum=a+b;printf("%dn",sum);3、求两个整数中的较大者#include <stdio.h>void main()int max(int x,int y);int a,b,c;scanf(

2、"%d,%d",&a,&b);c=max(a,b);printf("max=%d",c);int max(int x,int y)int z;if(x>y)z=x;elsez=y;return(z);4、编写一个程序，输入a,b,c三个值，输出其中最大者#include <stdio.h>void main()int a,b,c,max; printf("input a,b,c:n"); scanf("%d,%d,%d",&a,&b,&c); max=a;

3、if(max<b) max=b; if(max<c) max=c; printf("最大数是%dn",max);5、求5！#include <stdio.h>void main()int t=1,i=2; while(i<=5) t=t*i; i=i+1; printf("%dn",t);6、求多项式1-1/2+1/3-1/4+1/99-1/100的值#include <stdio.h>void main() int sign=1; double deno=2.0,sum=1.0,term; while(deno

4、<=100) sign=-sign; term=sign/deno; sum=sum+term; deno=deno+1; printf("%fn",sum);7、将华氏温度64°F转换为摄氏度#include <stdio.h>void main() float f,c; f=64.0; c=(5.0/9.0)*(f-32); printf("c=%fn",c);8、1000元存一年：（1）活期，年利率为r1；（2）一年期顶起，年利率r2；（3）存两次半年定期，年利率为r3.分别计算3种方法本息和#include <s

5、tdio.h>void main() float p0=1000,r1=0.0036,r2=0.0225,r3=0.0193,p1,p2,p3; p1=p0*(1+r1); p2=p0*(1+r2); p3=p0*(1+r3/2)*(1+r3/2); printf("p1=%fnp2=%fnp3=%fn",p1,p2,p3);9、给定一个大写字母A，输出其小写字母#include <stdio.h>void main()char c1,c2;c1='A'c2=c1+32;printf("%cn",c2);printf(&

6、quot;%dn",c2);10、给出三角形三边长，求面积#include <stdio.h>#include <math.h>int main()double a,b,c,s,area;a=3.67;b=5.43;c=6.21;s=(a+b+c)/2;area=sqrt(s*(s-a)*(s-b)*(s-c);printf("a=%ftb=%ftc=%fn",a,b,c);printf("area=%fn",area);11、输入一个double类型的数，使该数保留小数点后两位，对第三位小数进行四舍五入后处理，然后输出

7、此数，以便验证处理是否正确。#include<stdio.h>void main()double x;printf("Enter x:");scanf("%lf",&x);printf("(1)x=%fn",x);x=x*100+0.5;x=(int)x;x=x/100;printf("(2)x=%fn",x);12、编程从键盘输入两个整数给变量x和y，然后输出x和y的值，最后交换x和y的值并输出。#include<stdio.h>void main()int x,y,t;print

8、f("Enter x,y:n");scanf("%d %d",&x,&y);printf("x=%d y=%dn",x,y);t=x;x=y;y=t;printf("x=%d y=%dn",x,y);13、从键盘输入两个两位的正整数给变量x和y，并将x和y合并形成一个整数放在变量z中。合并的方式是：将数x的十位和各位依次放在z的千位和十位，将y的十位和个位放在z的个位和百位上。#include<stdio.h>void main()int x,y,z;printf("Input

9、 x,y:");scanf("%d,%d",&x,&y);x=x%100;y=y%100;z=(x/10)*1000+(x%10)*10+y/10+(y%10)*100;printf("x=%d,y=%d,z=%dn",x,y,z);14、输入3个整数，分别放入在变量a，b，c中，程序把输入的数据重新按由从小到大的顺序放在变量a，b，c中，最后输出a，b，c中的值#include<stdio.h>void main()int a,b,c,t;printf("input a,b,c:");scanf

10、("%d%d%d",&a,&b,&c);printf("a=%d,b=%d,c=%dn",a,b,c);if(a>b)t=a;a=b;b=t;if(a>c)t=a;a=c;c=t;if(b>c)t=b;b=c;c=t;printf("a=%d,b=%d,c=%dn",a,b,c);15、根据输入的学生成绩，给出相应的等级，90分以上的等级为A，60以下为E，其余每10分一个等级。#include<stdio.h>void main()int g;printf("Enter

11、 g:");scanf("%d",&g);printf("g=%d:",g);if(g>=90) printf("An");else if(g>=80) printf("Bn");else if(g>=70) printf("Cn");else if(g>=60) printf("Dn");else printf("En");#include<stdio.h>void main()int g;print

12、f("Enter g:");scanf("%d",&g);printf("g=%d:",g);switch(g/10)case 9: printf("An");break;case 8: printf("Bn");break;case 7: printf("Cn");break;case 6: printf("Dn");break;default: printf("En");16、平面点M(x,y),若M落在圆心在坐标原点单位圆

13、上，key=1；圆外，key=2；圆内key=0#include<stdio.h>#include<math.h>void main()float x,y,r;int key;printf("input x,y:"); scanf("%f,%f",&x,&y);r=sqrt(x*x+y*y);if(r>1) key=2;else if(r=1) key=1;else if(r<1) key=0; printf("(%.1f,%.1f):%dn",x,y,key); -1，x<0

14、 17、编写一个程序实现符号函数y=0,x=0 的功能 1，x>0#include<stdio.h>void main()int x,y;printf("Enter x:"); scanf("%d",&x);if(x<0) y=-1;elseif(x=0) y=0; elsey=1; printf("x=%d，y=%dn",x,y);#include<stdio.h>void main()int x,y;printf("Enter x:"); scanf("%d

15、",&x); y=-1; if(x!=0) if(x>0)y=1;elsey=0; printf("x=%d,y=%dn",x,y);18、判定某年是否闰年。#include<stdio.h>void main()int year,leap;printf("input the year:");scanf("%d",&year);if(year%4=0&&year%100!=0)|(year%400=0) leap=1;else leap=0;if(leap=1)printf(

16、"%d is a leap yearn",year);elseprintf("%d is not a leap yearn",year);#include<stdio.h>void main()int year,leap;printf("input the year:");scanf("%d",&year);if(year%4=0)if(year%100!=0)leap=1;elseif(year%400=0)leap=1;elseleap=0;elseleap=0;if(leap=1)prin

17、tf("%d is a leap yearn",year);elseprintf("%d is not a leap yearn",year); #include<stdio.h>void main()int year,leap;printf("input the year:");scanf("%d",&year);if(year%400=0) leap=1;elseif(year%4=0)if(year%100=0)leap=0;else leap=1;else leap=1;if(leap=

18、1)printf("%d is a leap yearn",year);elseprintf("%d is not a leap yearn",year);#include<stdio.h>void main()int year,leap;printf("input the year:");scanf("%d",&year);if(year%4!=0) leap=0;else if(year%100=0) leap=0;else if(year%400=0) leap=1;else leap=1

19、;if(leap=1)printf("%d is a leap yearn",year);elseprintf("%d is not a leap yearn",year);19、求一元二次方程ax2+bx+c=0的解。分析：a=0，非二次方程 b*b-4*a*c=0 ,两个相等实根 >0,两个不等实根 <0,两个共轭复根#include<stdio.h>#include<math.h>void main()float a,b,c,disc,x1,x2,realpart,imagpart;printf("in

20、put a,b,c:");scanf("%f,%f,%f",&a,&b,&c);printf("The equation"); if(fabs(a)<=1E-6)printf("is not quadraticn");else disc=b*b-4*a*c;if(fabs(disc)<=1E-6) printf("has two equal root:%8.4f",-b/(2*a);elseif(disc>1E-6)x1=(-b+sqrt(disc)/(2*a);

21、x2=(-b+sqrt(disc)/(2*a);printf("has distinct real roots:%8.4f and %8.4fn",x1,x2); elserealpart=-b/(2*a);imagpart=sqrt(-disc)/(2*a);printf("has complex roots:n");printf("%8.4f+%8.4fin",realpart,imagpart);printf("%8.4f-%8.4fin",realpart,imagpart);20、编写程序，从键盘输入一个

22、以秒为单位的时间数，将其换算成几小时几分几秒，然后输出。#include<stdio.h>void main() int x,h,m,s;scanf("%d",&x);h=x/3600;m=x%3600/60;s=x%60;printf("%ds=%d:%d:%d!n",x,h,m,s);21、任意输入一个字符，若是大写字母将其转换成小写字母#include<stdio.h>void main()char ch;ch=getchar();ch=(ch>='A'&&ch<='

23、;Z')?ch+32:'x'if(ch!='*')putchar(ch);putchar('n');22、编写程序，输入能代表一个日期的3个整数，计算并输出该日是改年的第几天。#include<stdio.h>void main()int y,m,d,dd=0;printf("Enter y/m/d:"); scanf("%d/%d/%d",&y,&m,&d);printf("%d/%d/%d",y,m,d);switch(m-1)case 1

24、1: dd=dd+30;case 10: dd=dd+31;case 9: dd=dd+30;case 8: dd=dd+31;case 7: dd=dd+31;case 6: dd=dd+30;case 5: dd=dd+31;case 4: dd=dd+30;case 3: dd=dd+31;case 2: dd=dd+28;case 1: dd=dd+31;case 0: dd=dd+d;if(m>2)&&(y%4=0&&y%100!=0|y%400=0)dd=dd+1;printf(" %dn",dd);23、当一个人的月收入在

25、2000元以下时免税；月收入在2000元到5000元之间时，超过2000的部分纳税8%；月收入在5000元以上时，2000至5000之间的部分纳税8%，超过5000的部分纳税15%。编写程序从键盘输入月收入income，计算并输出应交税款tax。#include "stdio.h"main()int income;float tax; printf("enter income:");scanf("%d",&income);if(income<=2000)tax=0;else if(income<=5000)tax=

26、0.08*(income-2000);elsetax=0.08*3000+0.15*(income-5000);printf("tax=%fn",tax);24、回文是指正读和反读都一样的数或字符串。例如：12321、55455、35553等都是回文。请编写一个程序，从键盘上读取一个包含五位数字的长整数，并判断它是否是回文。（提示：用除法运算和求余运算把一个数的个位、十位、百位、千位等分别分离出来。）#include "stdio.h"main()long x;int a,b,d,e;printf("enter x:");scanf(

27、"%ld",&x);a=x/10000;b=x%10000/1000;d=x%100/10;e=x%10;if(a=e&&b=d)printf("%ld is a huiwenn",x);elseprintf("%ld is not a huiwenn",x);25、设计一个简单的计算器，完成两个数的加减乘除分析：输入二个数及运算符 switch表达式：运算符 常量：'+''-''*''/'#include<stdio.h>void m

28、ain()float x,y;char op;printf("enter x,op,y:");scanf("%f %c %f",&x,&op,&y);switch(op)case '+':printf("%.2f%c%.2f=%.2fn",x,op,y,x+y);break;case '-':printf("%.2f%c%.2f=%.2fn",x,op,y,x-y);break;case '*':printf("%.2f%c%.2f=

29、%.2fn",x,op,y,x*y);break;case '/':if(y=0)printf("errorn");elseprintf("%.2f%c%.2f=%.2fn",x,op,y,x/y);break;26、编写程序，求1+2+3+。+100的值#include<stdio.h>void main() int i=1,sum=0; while(i<=100) sum=sum+i; i+; printf("sum=%dn",sum);#include<stdio.h>vo

30、id main() int i=1,sum=0; do sum=sum+i; i+; while(i<=100); printf("sum=%dn",sum);#include<stdio.h>main() int i,sum; for(i=1,sum=0;i<=100;i+) sum=sum+i; printf("sum=%dn",sum);27、求100以内奇偶数之和#include<stdio.h>void main() int n=1,odd=0,even=0; while(n<100) odd+=n;

31、even+=n+1; n+=2; printf("odd和=%d,even和=%dn",odd,even);28、求两个正整数m和n，求最大公约数和最小公倍数分析：1、用辗转相除法求最大公约数2、最小公倍数=两数积/最大公约数#include<stdio.h>void main() int m,n,m1,n1,a; printf("输入两个正整数:n"); scanf("%d,%d",&m,&n); m1=m;n1=n; a=m1%n1; while(a!=0) m1=n1;n1=a;a=m1%n1; pr

32、intf("最大公约数是%dn",n1); printf("最小公倍数是%dn",m*n/n1);29、求n！#include<stdio.h>main() int i,n; long s=1; printf("enter n:"); scanf("%d",&n); for(i=1;i<=n;i+) s=s*i; printf("%d!=%ldn",n,s);30、编写一个程序，计算半径为0.5，1.5,2.5,3.5,4.5,5.5mm时的圆面积#include<

33、;stdio.h>main()float r,s;for(r=0.5;r<=5.5;r+)s=3.14159*r*r;printf("r=%f s=%fn",r,s);31、循环嵌套的应用输出九九乘法表#include<stdio.h>main()int i,j;for(i=1;i<=9;i+)for(j=1;j<=i;j+)printf("%d*%d=%d ",i,j,i*j);printf("n");#include<stdio.h>main()int m,n;m=1;while(m

34、<=9) n=1; while(n<=m) printf("%d*%d=%d ",m,n,m*n); n+; printf("n");m+;32、找所有三位数 要求其百位数不大于2将个位与百位对换，得到的三位数是原三位数的2倍多分析：用三重循环控制变量分别表示百位数、十位数和个位数 百位数i取值12 十位数j取09 个位数k取29 n=100*i+10*j+k m=100*k+10*j+i 若m>=2*n并m<=3*n#include<stdio.h>main() int i,j,k,n,m,s=0; for(i=1;

35、i<=2;i+) for(j=0;j<=9;j+) for(k=2;k<=9;k+) n=100*i+10*j+k; m=100*k+10*j+i; if(m>+2*n&&m<3*n) +s; printf("%d ",n); if(s%10=0) printf("n"); 分析：用一重循环的循环控制变量i=101299百位数n1=i/100十位数n2=(i-n1*100)/10个位数n3=i-n1*100-n2*10m=100*n3+10*n2=n1m>=2*i并m<=3*i#include&l

36、t;stdio.h>main() int i,n1,n2,n3,m,s=0; for(i=101;i<=299;+i) n1=i/100; n2=(i-n1*100)/10; n3=i-n1*100-n2*10; m=100*n3+10*n2+n1; if(m>=2*i&&m<3*i) printf("%d ",i); s+; if(s%10=0) printf("n"); 33、在循环体中使用break语句#include<stdio.h>main()int i,s;s=0;for(i=1;i<

37、=10;i+)s+=i;if(s>5)break;printf("s=%dn",s);34、在循环体中使用continue语句#include<stdio.h>main() int i,s=0; for(i=1;i<=8;i+) s+=i; printf("ni=%d",i); if(i%2=0) continue; printf(" s=%dn",s); 35、从键盘输入全班的学习成绩，统计出最高分、最低分和平均分#include<stdio.h>main() int x,max,min,n; f

38、loat sum=0; max=0; min=100; n=0; printf("enter x(-1 to end):"); scanf("%d",&x); while(x>=0) sum=sum+x; n=n+1; if(x>max) max=x; if(x<min) min=x; scanf("%d",&x); if(max>0) printf("max=%d,min=%d,aver=%fn",max,min,sum/n);36、编程求输入的某个正整数是否为素数#inc

39、lude<stdio.h>main() int m,i,t; printf("enter a integer:"); scanf("%d",&m); for(i=2;i<=m-1;i+) if(m%i=0) t=0; break; else t=1; printf("%d:",m); if(t=1) printf("is a prime number!n"); else printf("is not a prime number!n");#include<stdi

40、o.h>#include<math.h>main()int m,i, k;scanf("%d",&m);k=sqrt(m);for(i=2;i<=k;i+)if(m%i=0) break;if(i>k)printf("%d是素数",m);else printf("%d是合数",m);37、求100200之间的素数#include<stdio.h>#include<math.h>main()int m,i,k,n=0;for(m=101;m<200;m=m+2)k=sq

41、rt(m);for(i=2;i<=k;i+)if(m%i=0) break;if(i>k)printf("%6d",m);n+; if(n%10=0)printf("n");38、公鸡5块一个，母鸡3块一个，小鸡3个一块，百元买百只，问分别多少只？分析：设公鸡x，母鸡y，小鸡z，x<=19#include<stdio.h>main()int x,y,z;for(x=0;x<=19;x+)for(z=0;z<=99;z=z+3)y=100-x-z;if(y>=0)&&(x*5+y*3+z/3=

42、100)printf("x=%d,y=%d,z=%dn",x,y,z);#include<stdio.h>main() int x=0,y,z; while(x<=19) y=0; while(y<=33) z=100-x-y; if(5*x+3*y+z/3=100) printf("x=%d y=%d z=%dn",x,y,z); y+; x+; 39、有一根长度为323米的钢材，要将它截取为两种规格a，b的长度分别为17米和27米的短料，每种至少一段，问分割成a，b各多少段后，剩余的残料r最少？#include<stdi

43、o.h>main()int na,nb,a,b,r,rmin;na=1;nb=1;rmin=323-17-27;for(na=1;na<=(323-27)/17;na+)nb=(323-na*17)/27;r=323-na*17-nb*27;if(r<rmin)rmin=r;a=na;b=nb;printf("a=%d,b=%d,min=%dn",a,b,rmin);40、猴子吃桃问题。小猴在某天摘桃若干个，当天吃掉一半，觉得还不过瘾，又多吃了一个；第二天吃了剩下桃子的一半又多一个；以后每天都这样吃下去，直到第8天要吃时只剩一个桃子了，问小猴子第一天共摘下

44、多少个桃子？分析：递推问题X(n-1)=(Xn+1)*2#include<stdio.h>main()int tao,n;tao=1;for(n=1;n<=7;n+)tao=(tao+1)*2;printf("tao(1)=%dn",tao);41、斐波那契数列：1，1,2,3,5,8,13,21.。此数列的第一项和第二项为1，从第三项开始，每一项为前两项之和。编程输出该数列的前15项，每行输出5个数。#include<stdio.h>main()int i,f1=1,f2=1,f3;printf("%5d%5d",f1,f

45、2);for(i=3;i<=15;i+)f3=f1+f2;printf("%5d",f3);if(i%5=0)printf("n");f1=f2;f2=f3;42、用公式pi/4=1-1/3+1/5-1/7.求pi的近似值，直到最后一项的绝对值小于10-4为止#include<stdio.h>#include<math.h>main()int n;float t,s,pi;pi=0; n=1;s=1.0;t=s/n;while(fabs(t)>=0.0001)pi=pi+t;n=n+2;s=-1*s;t=s/n;pri

46、ntf("pi=%fn",pi*4);#include<stdio.h>#include<math.h>main()float n,t1,t2,pi;pi=1; n=1;t2=1;while(fabs(t2)>=0.0001)n=n+4;t1=1/(n-2);t2=1/n;pi=pi-t1+t2;printf("pi=%fn",pi*4);43、高次方程求根。求方程3X3-4X2-5X+13=0的根#include<stdio.h>#include<math.h>main()float a,b,c,f

47、a,fb,fc;do printf("enter a,b:"); scanf("%f,%f",&a,&b); fa=3*a*a*a-4*a*a-5*a+13; fb=3*b*b*b-4*b*b-5*b+13;while(fa*fb>0);doc=(a+b)/2;fc=3*c*c*c-4*c*c-5*c+13;if(fa*fc>0) a=c;else b=c;while(fabs(fc)>0.0001);printf("3*x*x*x-4*x*x-5*x+13=0 nx=%f,f=%fn",c,fc);

48、44、编写程序，打印出所有的“水仙花数”（一个三位数各位数字立方和等于该数本身）#include<stdio.h>main()int a,b,c,x;for(x=100;x<=999;x+)a=x/100;b=x/10%10;c=x%10;if(x=a*a*a+b*b*b+c*c*c)printf("%d ",x); printf("n");打印出最大或最小的“水仙花数”#include<stdio.h>main()int a,b,c,x;for(x=999;x>=100;x-)a=x/100;b=x/10%10;c=

49、x%10;if(x=a*a*a+b*b*b+c*c*c)printf("%d ",x);break; printf("n");45、编写程序，输出从公元1980年至2880年所有的闰年年号。每输出5个年号换一行#include<stdio.h>main()int x,flag,s=0; for(x=1980;x<=2880;x+)flag=(x%4=0&&x%100!=0)|(x%400=0);if(flag)printf("%5d",x);s+;if(s%5=0)printf("n&quo

50、t;);45、数组的初始化#include<stdio.h>main()int a5=1,2,3,4,5;int b5=1,2,3;int c=1,2,3,4,5;static int d5;int e5;int i;for (i=0;i<5;i+)printf("%d",ai);printf("n"); for (i=0;i<5;i+)printf("%d",bi);printf("n"); for (i=0;i<5;i+)printf("%d",ci);prin

51、tf("n"); for (i=0;i<5;i+)printf("%d",di);printf("n"); for (i=0;i<5;i+)printf("%d",ei);printf("n");46、用数组来求fibonacci数列问题分析：fi=fi-2+fi-1 i=220#include<stdio.h>main()int i;static int f20=1,1;for (i=2;i<20;i+)fi=fi-2+fi-1;for (i=0;i<20;

52、i+)if(i%4=0) printf("n");printf("%6d",fi);47、统计全班某门功课期末考试的平均分和最高分（人数30）用简单变量：#include<stdio.h>#define N 30main() int i,sum=0,high=0,score; float average; printf("input everyone's score:n"); for(i=0;i<N;i+) scanf("%d",&score); sum+=score; if(sc

53、ore>high)high=score; average=(float)sum/N; printf("average=%fn",average); printf("highest=%dn",high);分析：*定义一个整形数组score30，存放全班同学分数 *用for循环读入分数，并求出总分和平均分 *定义变量high存放当前得到的“最高分”，每得到一个分数都要与high的值比较，若比high大，则放入high中。#include<stdio.h>#define N 30main()int i,sum=0,high,scoreN;fl

54、oat average;printf("input everyone's score:n");for(i=0;i<N;i+) for(high=0,i=0;i<N;i+)scanf("%d",&scorei); scanf("%d",&scorei);for(high=score0,i=0;i<N;i+) sum+=scorei;sum+=scorei; if(scorei>high)high=scorei;if(scorei>high)high=scorei;average=(f

55、loat)sum/N;printf("average=%fn",average);printf("highest=%dn",high);48、统计选票，设候选人有8人，编号为18，约定0为统计结束标志#include<stdio.h>main()static int x,n9;printf("input No.:");scanf("%d",&x);while(x)nx+=1;printf("input No.:");scanf("%d",&x);for(x