C语言必考100题(3)

13.

#include main() { char score; printf(\请输入五分制分数:\

scanf(\

switch(score) {

case 'A':printf(\case 'B':printf(\ break; case 'C':printf(\ break; case 'D':printf(\

case 'E':printf(\ } 14.

#include main() { }

15.

#include #include #include void main() {

int magic,guess,counter; int a,b; char op;

printf(\输入表达式：\scanf(\switch(op) {

case'+': printf(\case'-': printf(\ case'*': printf(\case'/': printf(\}

default:printf(\}

unsigned int seed; srand(time(NULL)); magic=rand()0+1; counter=0; do{

printf(\scanf(\

counter++; if(guess>magic) { }

16.

#include void main() { }

int i,p=1,n;

printf(\请输入数字：\scanf(\for(i=2;i<=n;i++) { }

p*=i;

} else { }

printf(\printf(\

}while(guess!=magic); printf(\

printf(\

printf(\

17.

#include long fact(long n); main() {

int n;

long result;

printf(\请输入数字：\scanf(\

}

result=fact(n);

if(result==-1) printf(\else printf(\

long fact(long n) { } 18.

#include #include main() {

double pi,sum=0,term,sign=1.0; int count=0,n=1; do{

term=sign/n; sum+=term; if(n<0) return -1; else if(n==0||n==1) return 1; else return (n*fact(n-1));

count++; sign=-sign; n+n+2;

}while(fabs(term)>=1e-4);

pi=sum*4;

printf(\

} 19.

#include main() {

int m,n;

for(m=1;m<10;m++) {

printf(\

}

printf(\

} 20.

for(m=1;m<10;m++) { printf(\}

printf(\for(m=1;m<10;m++) { }

for(n=1;n<=m;n++) { printf(\}

printf(\

#include void main() {

int i,j,k;

for(i=1;i<10;i++) { printf(\}

printf(\for(j=1;j<10;j++) { printf(\}

printf(\

for(i=1;i<10;i++) { }

for(k=10-i;k<9;k++) { }

printf(\

for(j=i;j<10;j++) {

printf(\}

printf(\

}

21.

#include #include main() { } 22.

#include #include int isprime(int n) {

int m;

for(m=2;m<=sqrt(n);++m) {

if(n%m==0) return 0; int i,n,s,flag=1;

printf(\请输入一个数：\scanf(\for(i=2;i

s=n%i;

if(s==0);flag=0;

}

if(flag) { }

else printf(\不是素数\\n\

printf(\是素数\\n\

}

printf(\

}

int main() {

int n,count=0;

for(n=2;n<=100;++n) {

isprime(n);