# include & ltstdio.h & gt
# include & ltstring.h & gt
int main()
{
int i,n,len
字符串[200];
gets(str);
len = strlen(str);
for(I = 0;我& ltleni++)
{
if(' a ' & lt;= str[I]& amp;& ampstr[I]& lt;='z ')
str[I]-= 32;
else if(' A ' & lt;= str[I]& amp;& ampstr[I]& lt;='Z ')
str[I]+= 32;
}
賣出(str);
返回0;
}
-
1.2
# include & ltstdio.h & gt
#定義N 3 //可改為50
int main()
{
int I;
int score[N][3];
int s[3]={0,0,0 };
Printf("輸入%d學生三門課的成績\n ",N);
for(I = 0;我& ltn;i++)
{
Printf("輸入%d學生三門課的成績\n ",I+1);
scanf("%d %d %d ",& amp分數[i][0],& ampscore[i][1],& amp得分[I][2]);
s[0]+= score[I][0];
s[1]+= score[I][1];
s[2]+= score[I][2];
}
Printf("%d名學生三門課總成績為:% d \ t% d \ t% d \ n ",n,s [0],s [1],s[2]);
printf("%d學生三門課的平均成績為:% .2f \ t% .2f \ t% .2f \ n ",n,s [0] * 1.0/n,s [1] * 1.0/n。
* 1.0/N);
返回0;
}
-
2.1
# include & ltstdio.h & gt
浮點fmin(浮點a,浮點b)
{
如果(a & ltb)返回a;
否則返回b;
}
int main()
{
float f1,f2,min
Printf("請輸入兩個實數:\ n ");
scanf("%f %f ",& ampf1。F2);
min=fmin(f1,F2);
Printf("其最小值為:%f\n ",min);
返回0;
}
-
2.2
# include & ltstdio.h & gt
#定義編號10
float f_ave(int a[])
{
int i,sum = 0;
浮動f;
for(I = 0;我& ltn;i++)sum+= a[I];
f = sum * 1.0/N;
返回f;
}
int main()
{
int I;
int SCO[N];
浮動大街;
Printf("請輸入10學生的分數:\ n ");
for(I = 0;我& ltn;i++) scanf("%d ",& ampSCO[I]);
ave = f _ ave(SCO);
Printf("%d名學生的平均成績為:%.2f\n ",N,ave);
返回0;
}
-
2.3
# include & ltstdio.h & gt
int gcd(int a,int b)
{
內部溫度;
如果(a & ltb)
{
temp = a;
a = b;
b =溫度;
}
如果(b == 0)
返回a;
其他
返回gcd(b,a % b);
}
int lcm(int a,int b)
{
返回a*b/gcd(a,b);
}
int main()
{
int a,b;
Printf("請輸入2個整數:\ n ");
scanf("%d %d ",& amp壹,& ampb);
Printf("其最小公倍數為:%d\n ",lcm(a,b));
返回0;
}
-
2.4
# include & ltstdio.h & gt
void d2b(int d)
{
int i,a,k = 0;
int w[100];
a = d;
while(a & gt;0)
{
w[k++]= a % 2;
a/= 2;
}
printf(" % d "的二進制表示為: ",d);
for(I = k-1;我& gt=0;i - ) printf("%d ",w[I]);
printf(" \ n ");
}
int main()
{
int a;
Printf("請輸入壹個10的十進制數:\ n ");
scanf("%d ",& ampa);
d2b(a);
返回0;
}
-
2.5
# include & ltstdio.h & gt
void Y_1(整數)
{
int I;
double y = 0.0
for(I = 1;我& lt= n;i++)y+= 1.0/I;
printf(" Y = 1+1/2+1/3……+1/% d = % . 2 lf \ n ",n,Y);
}
void Y_2()
{
int I;
long sum = 0;
for(I = 1;我& lt99;i++)sum+= I *(I+1)*(I+2);
printf(" Y = 1×2×3+2×3×4+……+98×99×100 = % LD \ n ",sum);
}
int main()
{
int n;
Printf("請輸入壹個值n:\ n ");
scanf("%d ",& ampn);
y _ 1(n);
y _ 2();
返回0;
}
-
3.1
# include & ltstdio.h & gt
int n;
float f_ave(int a[])
{
int i,sum = 0;
浮動平均= 0.0;
for(I = 0;我& ltn;i++)sum+= a[I];
ave = sum * 1.0/n;
返回大道;
}
int main()
{
int I;
int數組[200];
浮動大街;
Printf("請輸入數組的大小:\ n ");
scanf("%d ",& ampn);
for(I = 0;我& ltn;i++) scanf("%d ",& amparray[I]);
ave=f_ave(數組);
printf(" % d數組元素的平均值為:%.2f\n ",n,ave);
返回0;
}
3.2
# include & ltstdio.h & gt
# include & ltstring.h & gt
char *str_conn(char a[],char b[])
{
int i,len,len1,len 2;
字符串[200];
len 1 = strlen(a);
len 2 = strlen(b);
len = len 1+len 2;
for(I = 0;我& ltlen 1;i++)str[I]= a[I];
for(I = 0;我& ltlen2i++)str[len 1+I]= b[I];
str[len]= ' \ 0 ';
返回字符串;
}
int main()
{
int I;
char str1[100],str2[100],* str
Printf("請輸入第壹個字符串:\ n ");
scanf("%s ",str 1);
Printf("請輸入第二個字符串:\ n ");
scanf("%s ",str 2);
str=str_conn(str1,str 2);
Printf("串接的字符串是:%s\n ",str);
返回0;
}
3.4
# include & ltstdio.h & gt
int main()
{
int i,j,n,sum,temp
sum = 0;
Printf("請輸入數組的順序:\ n ");
scanf("%d ",& ampn);
Printf("請輸入%d*%d數組元素:\n ",n,n);
for(I = 0;我& ltn;i++)
{
for(j = 0;j & ltn;j++)
{
scanf("%d ",& amptemp);
if(I = = j)sum+= temp;
}
}
Printf("數組主對角線元素之和為:%d\n ",sum);
返回0;
}
3.5
# include & ltstdio.h & gt
# include & ltstring.h & gt
int countc(char s[])
{
int i,n,len
len = strlen(s);
n = 0;
for(I = 0;我& ltleni++)
{
if(' A ' & lt;= s[I]& amp;& amps[I]& lt;= ' Z ')n++;
}
返回n;
}
int main()
{
int n;
字符串[200];
Printf("請輸入壹個字符串:\ n ");
gets(str);
n = countc(str);
Printf("字符串中大寫字母的個數為:%d\n ",n);
返回0;
}
3.6
# include & ltstdio.h & gt
# include & ltstring.h & gt
void f(int x,int y,int z)
{
浮點rst = 0.0
if(x = = y & amp;& ampz==y)
{
Printf("非法計算,分母為0!\ n ");
}
其他
{
rst =(x+y)* 1.0/(x-y)+(z+y)* 1.0/(z-y);
printf("f(x,y,z)= % . 2f \ n ",rst);
}
}
int main()
{
int x,y,z;
Printf("請輸入X,Y,Z:\ n ");
scanf("%d %d %d ",& ampx & amp;y & amp;z);
f(x,y,z);
返回0;
}
3.7
# include & ltstdio.h & gt
# include & ltstring.h & gt
int ask_age(整數)
{
if(n==1)返回10;
else返回ask _ age(n-1)+2;
}
int main()
{
int n,年齡;
Printf("請輸入學生年齡:\ n ");
scanf("%d ",& ampn);
年齡= ask _ age(n);
Printf("這%d個學生的年齡是:%d\n ",n,年齡);
返回0;
}
-
4.1
# include & ltstdio.h & gt
int main()
{
int a,b,t;
int *p,*q,* tp
Printf("請輸入兩個int變量:\ n ");
scanf("%d %d ",& amp壹,& ampb);
p = & ampa;
q = & ampb;
{//交換p,q
TP = p;
p = q;
q = tp
}
{//交換p和q表示的變量
t = * p;
* p = * q;
* q = t;
}
Printf("交換後的兩個變量是:%d %d\n ",a,b);
返回0;
}
-
4.2
# include & ltstdio.h & gt
int main()
{
int i,m,n,p1,p2;
int a[100];
Printf("請輸入數組的大小:\ n ");
scanf("%d ",& ampn);
Printf("輸入%d個數組元素:\n ",n);
for(I = 0;我& ltn;i++) scanf("%d ",& ampa[I]);
Printf("輸入p,q指向數組元素的下標:\ n ");
scanf("%d %d ",& ampp1。p2);
m =(p 1+p2)/2;
printf(" p和q的中點r指向:a[%d],其值為%d\n ",m,a[m]);
返回0;
}
-
5.1
# include & ltstdio.h & gt
void s(int a[],int n)
{
int i,sum = 0;
int * p = a;
浮動大街;
for(I = 0;我& ltn;i++)
{
sum+= * p;
p++;
}
ave = sum * 1.0/n;
Printf("數組的平均值為:%.2f\n ",ave);
}
int main()
{
int i,n;
int a[100];
Printf("請輸入數組的大小:\ n ");
scanf("%d ",& ampn);
Printf("輸入%d個數組元素:\n ",n);
for(I = 0;我& ltn;i++) scanf("%d ",& ampa[I]);
s(a,n);
返回0;
}
-
5.2
# include & ltstdio.h & gt
int main()
{
int k;
字符串[200],* s;
Printf("請輸入壹個字符串:\ n ");
gets(str);
s = str
k = 0;
while(*s!='\0')
{
k++;
s++;
}
Printf("字符串長度為:%d\n ",k);
返回0;
}
-
5.3
# include & ltstdio.h & gt
int main()
{
int I;
float a[102],*min,* max
Printf("請輸入100實數:\ n ");
for(I = 0;我& lt100;i++) scanf("%f ",& ampa[I]);
min = a;
max = a;
for(I = 1;我& lt100;i++)
{
if(*(a+I)& gt;* max)max = a+I;
if(*(a+I)& lt;* min)min = a+I;
}
printf(" 100實數的最大值為:%.2f,最小值為:%.2f\n ",*max,* min);
返回0;
}
-
5.4
# include & ltstdio.h & gt
#定義編號10
void排序(int a[])
{
int i,j,TP;
int * p = a;
for(I = 0;我& ltn-1;i++)
{
for(j = I+1;j & ltn;j++)
{
if(*(p+I)& gt;*(p+j))
{
TP = *(p+I);
*(p+I)= *(p+j);
*(p+j)= TP;
}
}
}
}
int main()
{
int I;
int a[102],*min,* max
Printf("請輸入%d個整數:\n ",n);
for(I = 0;我& ltn;i++) scanf("%d ",& ampa[I]);
排序(a);
Printf("排序序列:\ n ");
for(I = 0;我& lt10;i++) printf("%d ",a[I]);
printf(" \ n ");
返回0;
}