c语言平时练习小例子.doc

给一个不多于4位的正整数，求出它是几位数，逆序打印出各位数字#includevoid main()int x,a,b,c,d;scanf(%d,&x);a=x/1000;b=x%1000/100;c=x%100/10;d=x%10;if(a!=0)printf(4:%d%d%d%dn,d,c,b,a);else if(b!=0)printf(3:%d%d%dn,d,c,b);else if(c!=0)printf(2:%d%dn,d,c);else if(d!=0)printf(1:%dn,d);从10至20之间的素数，自动输出（我的）#include#includevoid main()int x,k;for(x=10;x=10&x=20;x+)for(k=2;ksqrt(x)printf( %d ,x);0-9这十个数字组成多少个无重复的三位数#includevoid main()int x,a,b,c,num=0;for(x=100;x=999;x+)a=x/100;b=x/10%10;c=x%10;if(a!=b&a!=c&b!=c)num+;printf(%5d,x);printf(n number= %d,num);求300内能被17整除的最大数#includevoid main()int x;for(x=300;x=1;x-)if(x%17=0) break;printf(x=%dn,x);斐波那契数列#includevoid main()long f1=1,f2=1,f3;int k;printf(%1dt%1dt,f1,f2);for(k=3;k=30;k+)f3=f1+f2;printf(%dt,f3);f1=f2;f2=f3;求300以内能被17整除的所有整数，用continue#includevoid main()int x;for (x=1;x=300;x+)if(x%17!=0) continue;printf(%dt,x);输出三角形星花#include void main()int k1,k2;for(k1=1;k1=4;k1+)putchar(t);for(k2=1;k2=k1;k2+)putchar(b);for(k2=1;k2=k1*2-1;k2+)putchar(*);putchar(n);求s=2/1-3/2+5/3-8/5求前十项的和#includevoid main()float s=0,f1=2,f2=1,f=1,t,n;for(n=1;n=10;n+)s=s+f*f1/f2;f=f*(-1);t=f2;f2=f1;f1=f1+t;printf(s=%fn,s);逆序输出任意整数#include void main()long x,y;scanf(%d,&y);while(y!=0)x=y%10;printf(%d,x);y=y/10;函数求和#includevoid main()float add(float,float);float a,b,c;scanf(%f,%f,&a,&b);c=add(a,b);printf(sum is %f,c);float add(float x,float y)float z;z=x+y;return(z);输入年月日输出该天在该年的天数#includeint leap(int year)int lp;lp=(year%4=0&year%100!=0|year%400=0)?1:0;return lp;int month_day(int year,int month)int d;switch(month)case 1:case 3:case 5:case 7:case 8:case 10:case 12:d=31;break;case 2:d=leap(year)?29:28;break;default:d=30;return d;int days(int year,int month,int day)int i,ds=0;for(i=1;imonth;i+)ds=ds+month_day(year,i);ds=ds+day;return ds;void main()int year,month,day,t_day;scanf(%d_%d_%d,&year,&month,&day);t_day=days(year,month,day);printf(%d_%d_%d is %dn,year,month,day,t_day);计算x的n次方#includevoid main()float power(float x,int n);float x,y;int n;scanf(%f,%d,&x,&n);y=power(x,n);printf(%f,y);float power(float x,int n)int i;float t=1;for(i=1;i=n;i+)t=t*x;return t;求和#includevoid main()float add(float,float);float a,b,c;scanf(%f,%f,&a,&b);c=add(a,b);printf(sum is %f,c);float add(float x,float y)float z;z=x+y;return(z);交换两个数1（这个不能交换）#includevoid swap(int a,int b);void main()int x=7,y=11;printf(x=%d,ty=%dn,x,y);printf(swapped:n);swap(x,y);printf(x=%d,ty=%dn,x,y);void swap(int a,int b)int temp;temp=a;a=b;b=temp;交换两个数2（能换过来）#includevoid swap(int *p1,int *p2)int p;p=*p1;*p1=*p2;*p2=p;void main()int a,b;scanf(%d,%d,&a,&b);printf(a=%d,b=%dn,a,b);printf(swapped:n);swap(&a,&b);printf(a=%d,b=%dn,a,b);递归算法计算n！#include long fac(unsigned n)long f;if(n=0)f=1;else f=n*fac(n-1);return f;void main()long y;int n;scanf(%d,&n);y=fac(n);printf(%d!=%ldn,n,y);例5-1 输入10个数，正序逆序输出，用数组#includevoid main()int i;int a10;printf(input 10 numbersn);for(i=0;i10;i+)scanf(%d,&ai);printf(n);for(i=0;i=0;i-)printf(%d ,ai);利用数组，求斐波拉契数列的前10项#includevoid main()int i;static int a10=1,1;for(i=2;i10;i+)ai=ai-1+ai-2;for(i=1;i10;i+)printf(%d ,ai);求若干数（不多于10个）的最大数，最小数#define N 10#includevoid main()int i,n;float aN,max,min;printf(input data numbers);scanf(%d,&n);printf(enter numbers:);for(i=0;in;i+)scanf(%f,&ai);max=min=a0;for(i=1;imax) max=ai;if(aimin) min=ai;printf(nmax=%f,min=%fn,max,min);输入10个数，求它们的和#includevoid main()int a10;int i,sum=0;for(i=0;i=9;i+)printf(enter number %d:,i+1);scanf(%d,&ai);sum+=ai;printf(the totle is :%dn,sum);冒泡排序法#includevoid main()int a6;int i,j,t;printf(input 6 numbers:n);for(i=0;i6;i+)scanf(%d,&ai);printf(n);for(j=1;j6;j+)for(i=0;iai+1)t=ai;ai=ai+1;ai+1=t;printf(the sored numbers:n);for(i=0;i6;i+)printf(%d ,ai);printf(n);判断是否为回文数#includevoid main()long x;int i,j,n,d20;scanf(%ld,&x);n=0;dodn=x%10;x=x/10;n+;while(x!=0);for(i=0,j=n-1;ij;i+,j-)if(di!=dj) break;if(ij) printf(not);else printf(yes);二维数组的输入输出#includevoid main()int i,j,a34;printf(input array numbers:n);for(i=0;i3;i+)for(j=0;j4;j+)scanf(%d,&aij);printf(output array numbers:n);for(i=0;i3;i+)for(j=0;j4;j+)printf(%d ,aij);printf(n);N行M列二维数组找出最大值，及最大值所在行列#define N 2#define M 3#includevoid main()int i,j,xNM,max,line,col;printf(input array numbers:n);for(i=0;iN;i+)for(j=0;jM;j+)scanf(%d,&xij);max=x00;line=0;col=0;for(i=0;iN;i+)for(j=0;jM;j+)if(maxxij)max=xij;line=i;col=j;printf(nmax=%dtline=%dtcol=%dn,max,line,col);输入字符串，统计小写大写字母、数字、其他字符的个数#includevoid main()int i,m,n,x,y;char s80;printf(input a string:n);scanf(%s,s);m=n=x=y=0;i=0;while(si!=0)if(si=a&si=A&si=0&si=9) x+;else y+;i+;printf(az:%dnAZ:%dn09:%dnothers:%dn,m,n,x,y);将字符串S1从第m个字符开始剩余的所有字符，送入字符数组s2中#includevoid main()int i,j,m;char s180,s280;printf(input a string:n);gets(s1);printf(input start point:n);scanf(%d,&m);i=m-1;j=0;while(s1i!=0)s2j=s1i;i+;j+;s2j=0;puts(s2);字符串拷贝函数#include#includevoid main()static char a10=abcdefghi;char b=happy; strcpy(a,b);puts(a);字符串连接函数#include#includevoid main()static char a20=my name is ,b10=li ming;strcat(a,b);puts(a);计算字符串长度的函数：#include#includevoid main()static char st20=hello0abcd0abc0;printf(%d,strlen(st);（去掉hello后的那些，结果也是5）用字符串处理函数，判断回文数#include#includevoid main()char a10;int i,j,n,f=1;gets(a);n=strlen(a);for(i=0,j=n-1;ij;i+,j-)if(ai!=aj)f=0;break;if(f=1)printf(yes);一个数组10个整形元素，求出各素数之和（数组元素作为函数的参数）#include#includevoid main()int a10,i,sum=0;int prime(int x);printf(enter 10 numbers:n);for(i=0;i10;i+)scanf(%d,&ai);if(prime(ai) （prime(ai)返回的值只是1或0，若是0，则if错误，就不进行下一步sum+=ai。若是1，则进行下一步。）sum+=ai;printf(sum=%dn,sum);int prime(int x)int f=1,k;if(x=1) f=0;for(k=2;k=sqrt(x);k+)if(x%k=0)f=0;break;return(f);数组名作为函数的参数（计算一个数组中的某几项的和）#includeint f(int b,int m,int n)int i,s=0;for(i=m;in;i=i+2)s=s+bi;return s;void main()int x,a=1,2,3,4,5,6,7,8,9;x=f(a,3,7);printf(%dn,x);【指针】* 求其后内存地址中的内容#includestdio.hvoid main()int a,b;int *p1,*p2;a=100;b=10;p1=&a;p2=&b;printf(%d,%dn,a,b);printf(%d,%dn,*p1,*p2);对输入的两个整数按大小顺序输出#include void main()int *p1,*p2,*p,a,b;a=5;b=9;p1=&a;p2=&b;if(ab)p=p1;p1=p2;p2=p;printf(a=%d,b=%dn,a,b);printf(max=%d,min=%dn,*p1,*p2);交换两数1，能#includevoid main()void swap(int *pa,int *pb);int a,b;int *p1,*p2;scanf(%d,%d,&a,&b);p1=&a;p2=&b;if(ab)swap(p1,p2);printf(n%d,%dn,a,b);void swap(int *pa,int *pb)int p;p=*pa;*pa=*pb;*pb=p;交换两数2，能#includevoid main()int a,b;void swap(int *pa,int *pb);scanf(%d,%d,&a,&b);if(ab)swap(&a,&b);printf(n%d,%dn,a,b);void swap(int *pa,int *pb)int p;p=*pa;*pa=*pb;*pb=p;交换两数3，不能#includevoid main()int a,b;int *p1,*p2;void swap(int *pa,int *pb);scanf(%d,%d,&a,&b);p1=&a;p2=&b;if(ab)swap(p1,p2);printf(n%d,%dn,a