1、精選文檔1將成績分為A，B，C等的程序#include<stdio.h>void main()int score;char grade;printf("Please input a score:n");scanf("%d",&score);grade=score>=90?'A':(score>=60?'B':'C');printf("%d belongs to %cn",score,grade);2判斷是數字，字母，還是其他字符#include<st

2、dio.h>void main()char c;printf("Please input a character:");c=getchar();if(c>='A'&&c<='Z'|c>='a'&&c<='z')printf("%c is lettern",c);else if(c>='0'&&c<='9')printf("%c is digitn",c

3、);else printf("%c is other charactern",c);3三角形面積#include<stdio.h>#include<math.h>void main()float a,b,c,s,area;scanf("%f,%f,%f",&a,&b,&c);s=(a+b+c)/2.0;area=sqrt(s*(s-a)*(s-b)*(s-c);printf("a=%7.2f,b=%7.2f,c=%7.2fn",a,b,c);printf("area=%7.2f

4、,s=%7.2fn",area,s);4輸入數字，即可得到相應星期單詞#include<stdio.h>void main()int x;printf("Input integer number:");scanf("%d",&x);switch(x)case 1:printf("Mondayn");break;case 2:printf("Tuesdayn");break;case 3:printf("Wednesdayn");break;case 4:printf

5、("Thursday");break;case 5:printf("Fridayn");break;case 6:printf("Saturdayn");break;case 7:printf("Sundayn");break;default: printf("errorn");5圓的周長，面積，球的體積，表面積，圓柱體積#include<stdio.h>#define PI 3.1415926void main()float r,h,l,s,sq,vq,vz;printf(&quo

6、t;請輸入圓半徑r,圓柱高h:n");scanf("%f,%f",&r,&h);l=2*PI*r;s=PI*r*r;sq=4*PI*r*r;vq=4.0/3.0*PI*r*r*r;vz=PI*r*r*h;printf("圓周長： l=%6.2fn",l);printf("圓面積： s=%6.2fn",s);printf("圓球表面積：sq=%6.2fn",sq);printf("圓球體積： sv=%6.2fn",vq);printf("圓柱體積： sz=%6.

7、2fn",vz);6某分段函數，輸入X求解Y的值#include<stdio.h>void main()float x,y;printf("Please input x:");scanf("&f",&x);if(x<-1)y=1;elseif(x<=1)y=2*x-5;elsey=5*x*x-1;printf("y=%10fn",y);7比較輸入的兩個數，并輸出較大值#include<stdio.h>void main() float x,y,max;printf(&quo

8、t;Please input two number x,y:");scanf("%f,%f",&x,&y);if(x>y) max=x;else max=y;printf("max=%7.2f",max);例5.10 求兩個整數的最大公約數和最小公倍數。#include<stdio.h>void main( )int m,n,p,t,r;scanf(“%d,%d”,&m,&n);if(n<m)t=n;n=m;m=t;p=m*n;while(m!=0)

9、r=n%m;n=m;m=r;printf(“m和n的最大公約數：%dn”,n)；printf(“m和n的最小公倍數：%dn”,p/n)；課后2、計算1-10之間的奇數和偶數之和并分別輸出。#include<stdio.h>void main( )int  a,b,c,i;a=c=0;for(i=0;i<=10;i+=2;)a+=I;b=i+1;c+=b;printf(“偶數之和=%dn”,a);printf(“奇數之和=%dn”,c-11);3、求100-200間的全部素數并輸出，輸出十個數后換行。#include<stdio.h

10、>#include<math.h>void main( )int m,flag,i,n;for(m=101;m<200;m=m+2;)flag=1;for(i=2;i<sqrt(m);i+)if(m%i=0)flag=0;break;if(flag= =1)printf(“%d”,m);N=n+1If(n%10=0) printf(“n”); 4、輸出100以內能被3整除且個位數為6的所有整數。#include<stdio.h>void main( )int i,

11、j;for(i=0;i<=9;i+)j=i*10+6;if(j%3!=0)   continue;printf(“%d”,j);printf(“%n”);例6.4應用冒泡排序法將數組中的五個數據按升序排列。#include<stdio.h>void main( )int i,j,t,a5；printf（“please input the array:”）;for(i=0;i<5;i+)scanf(“%d”,&ai);for(i=0;i<4;i+)for(j=0;j&l

12、t;4-I;j+)if(aj>aj+1)t=aj;aj=aj+1;aj+1=t;printf(“the result is:”);for(i=0；i<5;i+)printf(“%d”,ai);printf(“n”)例6.7將3*4的二維數組中的第0列和最后一列的元素的數值交換，第一列和第二列元素的值相交換。#include<stdio.h>void main( )int a34=5,8,9,1,4,2,6,7,12,13,14,10,i,j,k;for(i=0;i<3;i+)for(j=0;j<4/2;j+)

13、k=aij;aij=ai3-j;ai3-j=k;for(i=0;i<3;i+)printf(“n”);for(j=0;j<4;j+)printf(“%4d”,aij);printf(“n”);例6.8求3*3矩陣主對角線和次對角線上各元素之和。#include<stdio.h>void main( )int a33=1,2,3,4,5,6,7,8,9,I,j,sum=0;for(i=0;i<3;i+)sum+=aij;for(i=0;i<3;i+)for(j=2;j>=0;j-)if(i+j=2)sum+= ai

14、j;sum=sum-a3/23/2;printf(“sum=%dn”,sum); 請編寫函數fun，其功能是 求2+4+6+8+20 的和#include<stdio.h>void NONO();int fun()int sum=0;for(int i=2;i<21;i+)sum+=i;i+;return sum;void main()printf("%dn",fun();NONO();void NONO()FILE *wf;wf=fopen("j5.out","w");fprintf(wf,"%dn&qu

15、ot;,fun();fclose(wf);用指向二維數組元素的指針變量，找出二維數組中值最大的元素，并指出。#include<stdio.h>void main()int a34=1,2,3,4,5,6,7,8,9,10,11,12;int *p;int max;max=a00;for(p=&a00;p<&a00+12;p+)if (*p>max) max=*p;printf("max=%dn",max);用字符型指針變量輸出字符數組中的字符串#include<stdio.h>void main()char s="

16、;HELLO!"char *p;p=s;while(*p!='0')printf("%c",*p);p+；printf("n");定義一個求字符串長度的函數，輸出由鍵盤輸入的字符串的長度。#include<stdio.h>#include<string.h>int mystrlen(char *s)int len=0;while(*s+)len+;return len;void main()int k;char a80;gets(a);k=mystrlen(a);printf("%dn"

17、;,k);把“FORTRAN”、“BASIC”、“C+”、“VB”、“C”五個字符串，用指針數組存放它們的首地址，并用指向指針的指針變量把它們輸出。#include<stdio.h>void main()int i;char *c5="FORTRAN","BASIC","C+","VB","C"char *p;p=c;for(i=0;i<5;i+)printf("%sn",*p);p+;調用max函數返回數組各元素中值最大的元素地址。#include<

18、stdio.h>int *max(int b,int n)int i,*q=b;for(i=1;i<n;i+)if(*q<bi) q=b+i;return q;void main()int *p,a10=-7,5,19,13,14,38,-2,11,10,-6;p=max(a,10);printf("max:%dn",*p);用指針變量指向一維數組中的最大值，并輸出最大值。#include<stdio.h>void main()int a8=-2,8,9,12,15,17,25,-8;int i,*p;p=a;for(i=1;i<8;i+

19、)if(*p<ai) p=&ai;printf("%dn",*p);例4.9編寫程序，判斷某一年是否是閏年#include<stdio.h>void main( )int year ,flag;printf(“Please input year:”);scanf(“%d”,&year);if(year%4=0)if(year%100= =0)if(year%400= =0)flag=1;elseflag=0;elseflag=1;elseflag=0;if(flag)printf(“%d is a leap yearn”,year);els

20、eprintf(“%d is not a leap yearn”,year);2.輸出一個字符，判別它是否是大寫字母，如果是大寫字母，將其轉換為小寫字母，否則就不轉換，最后輸出#include<stdio.h>void main( )char ch;scanf（“%c”,&ch）;ch=(ch>=A&&ch<=Z?(ch+32):ch);printf(“%c”,ch);3.有一個函數：y=x (x<1)2x-1 (1<=x<10)3x-11 (x>=10)根據該分段函數寫程序，輸入一個x，輸出對應y的值#include<stdio.h>void main( )float x,y;printf(“Please input x:”);scanf(“%f”,&x);if(x<1)y=x;else if(x<10)y=2*x-1;elsey=3*x-11;printf(“y=%10fn”,y);例5.4 任意輸入10個整數，找出其中最大值并輸出#include<sdio.h>void main( )int a,