C语言大一答案

1．#include int main() {int x,y;

printf(\"input x:\"); scanf(\"%d\if(x<0||x>100) y=-1; else if(x==0) y=0; else y=1;

printf(\"%d\\n\return 0; }

2. #include int main() {float a,b,c,t;

printf(\"please enter three number:\"); scanf(\"%f,%f,%f\if(a{t=a;a=b;b=t;} if(a{t=a;a=c;c=t;} if(b{t=b;b=c;c=t;}

printf(\"%f,%f,%f\return 0; }

3. #include int main()

{float a,b,c,d,max,min;

printf(\"please enter four number:\"); scanf(\"%f,%f,%f,%f\max=(a>b)?a:b;

max=(max>c)?max:c; max=(max>d)?max:d; min=(amin=(minmin=(min4 #include int main() {

int score; char grade;

scanf(\"%d\if(score<0||score>100)

{printf(\"输入数据有误请重输!\\n\"); scanf(\"%d\}

score=score/10;

switch (score) {case 10:

case 9:grade='A';break; case 8:grade='B';break; case 7:grade='C';break; case 6:grade='D';break; case 5: case 4: case 3: case 2: case 1:

case 0:grade='E';break;

}printf(\"grade=%c\\n\return 0; }

#4#include int main()

{int score;char grade;

printf(\"please enter score:\"); scanf(\"%d\

if(score>&&score<=100) grade='A'; else

if(score>79&&score<90) grade='B';

else

if(score>69&&score<80) grade='C'; else

if(score>59&&score<70) grade='D'; else

if(score>=0&&score<60) grade='E'; else

printf(\"enter data error.\\n\"); printf(\"%c\\n\return 0; }

5. #include int main() {float x,y;

scanf(\"%f\if(x<1) y=x; else

if(x==10) y=(3*x-11); else

y=(2*x-1);

printf(\"%f\\n\return 0; }

6. #include #include int main()

{int n,i,m=0;double k; for(n=301;n<=400;n=n+2) {k=sqrt(n);

for(i=2;i<=k;i++) if(n%i==0)break; if(i>k+1)

{printf(\"%d\m=m+1; }

if(m%5==0) printf(\"\\n\"); }

printf(\"\\n\");

return 0; }

7. #include int main()

{int f1=1,f2=1,i; for(i=1;i<=10;i++)

{printf(\"%12d,%12d\if(i%2==0)printf(\"\\n\"); f1=f1+f2; f2=f2+f1;} return 0; }