i wrote continue which brings back control to iteration and until the remainder is not zero so output should be printed. but it is not . why ?
#include<stdio.h>
main()
{
int n,i;
scanf("%d",&n);
for(i=2;i<n;i++)
{
if(n%i!=0)
{
continue;
printf("prime\n");
}
}
}
Can you spot the difference?
int main(void)
{
int n,i;
scanf("%d",&n);
for(i=2;i<n;i++)
{
if(n%i!=0)
{
continue;
}
else
{
printf("not prime\n");
return 0;
}
}
printf("prime\n");
}
Related
I am trying to solve a problem of HackerRank. The problem wants me to find out if a string can be changed into a palindrome string or not with a certain number of changing characters of that string. That certain number will be given by input. I am giving the link of full description of the problem below.
In my code, I first checked if the string is already palindrome or not. Then I checked some cases under the first checking for the given number of changes to find out if that string can be changed into palindrome after changing the characters.
But I am getting different output for my code. Output that I found from code blocks is not the same as the output which I found in HackerRank.
Here is the link of the full problem statement
my code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
void print(char str[],int n)
{
int i;
for(i=0;i<n;i++)
{
printf("%c",str[i]);
}
}
void cpy(char qtr[],char str[],int n)
{
int i;
for(i=0;i<n;i++)
{
qtr[i]=str[i];
}
}
void rev(char str[],int n)
{
int i;
char qtr[100000];
for(i=0;i<n;i++)
{
qtr[i]=str[n-1-i];
}
for(i=0;i<n;i++)
{
str[i]=qtr[i];
}
}
int main()
{
char str[100],str2[100000],qtr[100000],c;
int n,k,i;
scanf("%d",&n);
scanf("%d",&k);
fflush(stdin);
gets(str);
cpy(qtr,str,n);
rev(str,n);
cpy(str2,str,n);
int same=0;
if(strcmp(str2,qtr)==0)
{
same=1;
}
if(k==n)
{
c=qtr[i]+1;
for(i=0;i<k;i++)
{
if(qtr[i]==c)
{
c=c+1;
i=-1;
continue;
}
}
for(i=0;i<k;i++){qtr[i]=c;}
print(qtr,n);
return 0;
}
if(same==1)
{
if(n%2!=0)
{
if(qtr[n/2]!='9'){qtr[n/2]='9';}
else
{qtr[n/2]='1';}
k--;
for(i=0;i<n;i++)
{
if(k<0){printf("-1");break;}
if(k==0){printf(qtr,n);break;}
if(qtr[i]=='9')
{
qtr[i]='1';
qtr[n-1-i]='1';
k=k-2;
}
else
{
qtr[i]='9';
qtr[n-1-i]='9';
k=k-2;
}
}
}
else
{
for(i=0;i<n;i++)
{
if(k<0){printf("-1");break;}
if(k==0){print(qtr,n);break;}
if(qtr[i]=='9')
{
qtr[i]='1';
qtr[n-1-i]='1';
k=k-2;
}
else
{
qtr[i]='9';
qtr[n-1-i]='9';
k=k-2;
}
}
}
}
else
{
if(n%2==0)
{
int arr[n];
for(i=0;i<n;i++){arr[i]=0;}
while(k>=0)
{
int g=0;
for(i=0;i<n/2;i++)
{
if(qtr[i]!=qtr[n-i-1])
{
arr[i]=1;
arr[n-i-1]=1;
qtr[i]=qtr[n-i-1];
k--;
g=1;
}
}
if(k==0){print(qtr,n);return 0;}
if(k%2!=0)
{
for(i=0;i<n/2;i++)
{
if(arr[i]==1)
{
arr[i]=2;
qtr[i]=qtr[i]+1;
qtr[n-i-1]= qtr[i];
k--;g=1;
break;
}
}
}
if(k==0){print(qtr,n);return 0;}
if(k%2==0)
{
for(i=0;i<n/2;i++)
{
if(arr[i]==0)
{
arr[i]=3;
qtr[i]=qtr[i]+1;
qtr[n-i-1]= qtr[i];
k=k-2;g=1;
break;
}
}
}
if(k==0){print(qtr,n);return 0;}
if(g==1){printf("-1");return 0;}
}
printf("-1");return 0;
}
else
{
int arr[n];
for(i=0;i<n;i++){arr[i]=0;}
while(k>=0)
{
int g=0;
for(i=0;i<n/2;i++)
{
if(qtr[i]!=qtr[n-i-1])
{
arr[i]=1;
arr[n-i-1]=1;
qtr[i]=qtr[n-i-1];
k--;
g=1;
}
}
if(k==1){qtr[n/2]=qtr[n/2]+1;k--;print(qtr,n);return 0;}
if(k==0){print(qtr,n);return 0;}
if(k%2!=0)
{
for(i=0;i<n/2;i++)
{
if(arr[i]==1)
{
arr[i]=2;
qtr[i]=qtr[i]+1;
qtr[n-i-1]= qtr[i];
k--;g=1;
break;
}
}
}
if(k==1){qtr[n/2]=qtr[n/2]+1;k--;print(qtr,n);return 0;}
if(k==0){print(qtr,n);return 0;}
if(k%2==0)
{
for(i=0;i<n/2;i++)
{
if(arr[i]==0)
{
arr[i]=3;
qtr[i]=qtr[i]+1;
qtr[n-i-1]= qtr[i];
k=k-2;g=1;
break;
}
}
}
if(k==1){qtr[n/2]=qtr[n/2]+1;k--;print(qtr,n);return 0;}
if(k==0){print(qtr,n);return 0;}
if(g==1){printf("-1");return 0;}
}
printf("-1");return 0;
}
}
}
I've written a very simple program which calculate the factorial of a number, the problem is that from 30 to 60 approximately, it returns a negative number and from 70 it returns 0.
I don't what I've done wrong. Could this problem depend on the computing power of my computer?
Here's the code:
#include <stdio.h>
int main(){
int x, i;
long long int f = 1;
printf("Insert a number:");
scanf("%d", &x);
if (x == 0){
printf("0! = 1");
}
else {
for (i = 1; i <= x; i++){
f *= i;
}
printf("%d! รจ = %lli", x, f);
}
return 0;
}
Here is my code:
#include<stdio.h>
#include<math.h>
#include<stdlib.h>
void Carry(int bit[],int pos)
{
int i,carray=0;
for(i=0;i<=pos;i++)
{
bit[i]+=carray;
if(bit[i]<=9)
{
carray=0;
}
else if(bit[i]>9&&i<pos)
{
carray=bit[i]/10;
bit[i]%=10;
}
else if(bit[i]>9&&i>=pos)
{
while(bit[i]>9)
{
carray=bit[i]/10;
bit[i]%=10;
i++;
bit[i]=carray;
}
}
}
}
int main()
{
int num,pos,digit,i,j,m,n;
double sum=0;
int *fact;
printf("input want to calculute factorial num:");
scanf("%d",&num);
for(i=1;i<=num;i++)
{
sum+=log10(i);
}
digit=(int)sum+1;
if(!(fact=(int *)malloc((digit+1)*sizeof(int))))
{
printf("malloc failed\n");
return 0;
}
for(i=0;i<=digit;i++)
{
fact[i]=0;
}
fact[0]=1;
for(i=2;i<=num;i++)
{
for(j=digit;j>=0;j--)
{
if(fact[j]!=0)
{
pos=j;
break;
}
}
for(j=0;j<=pos;j++)
{
fact[j]*=i;
}
Carry(fact,pos);
}
for(j=digit;j>=0;j--)
{
if(fact[j]!=0)
{
pos=j;
break;
}
}
m=0;
n=0;
for(i=pos;i>=0;i--)
{
printf("%d",fact[i]);
m++;
if(m%4==0)
{
printf(" ");
}
if(m==40)
{
printf("\n");
m=0;
n++;
if(n==10)
{
printf("\n");
n=0;
}
}
}
printf("\n\n");
return 0;
}
#include <stdio.h>
int main()
{
int rev_num=0,x=0,n,a;
printf("Enter a number");
scanf("%d",&n);
for(int i=n+1;i<i+1;i++)
{
a=i;
while(a>0)
{
rev_num=rev_num*10+a%10;
a/=10;
}
for(int j=2;j<i;j++)
{
x=0;
if(i%j==0)
{
x=1;
break;
}
}
if(x==0 && i==rev_num)
{
printf("%d is the next prime palindrome",i);
break;
}
}
return 0;
}
We have to find next prime palindrome of a number, but the code is not giving any o/p, nor any error. It just keeps asking for input indefintely.Why????
this is a solution of SPOJ's next pallindrome. the logic gives right solution in other ide but is rejected by the SPOJ.
what is the problem with this?
#include <stdio.h>
int pallin(int i){
int oint=i;
int re,rev=0;
while(oint!=0){
re=oint%10;
rev=rev*10+re;
oint/=10;
}
if(rev==i){
return rev;
}
else{
return 0;
}
}
int main(){
int i,num;
scanf("%d",&i);
while(i--){
scanf("%d",&num);
for(int n=num+1;n<100000;++n){
if(pallin(n)) {
printf("%d\n",pallin(n));
break;
}
else{
continue;
}
}
}
return 0;
}
i am pursuing the course on programming and data structures in nptel's MOOC.
A programming assignment in the course requires us to calculate sum of selected coefficients.
Now the program i wrote calculated the answer , but i am experiencing a runtime error.
Now i had this inclination of using gets() instead of scanf() so as to speed up my input.
how do i do that?
the code is as follows:
#include<stdio.h>
int combi(int ,int);
long fact(int);
int main()
{
int r,i,v[20],p[20],t,l=1,b=0,sum=0,a=0,flag=0;
char ch='a';
scanf("%d",&r);
scanf("%d",&t);
for(i=0;i<t;i++)
{
scanf("%d",&v[0]);
if(getchar()==' ')
{
if(r<v[0])
{
while(ch!='\n')
{
scanf("%d",&v[l]);
l++;
if(getchar()=='\n')
{
p[a]=-1;
a++;
l=1;
break;
}
}
}
else
{
while(ch!='\n')
{
scanf("%d",&v[l]);
if(v[l]>v[0])
{
flag=1;
}
l++;
if(getchar()=='\n')
{
if(flag>0)
{
p[a]=-1;
a++;
l=1;
sum=0;
flag=0;
break;
}
else
{
for(b=1;b<l;b++)
{
sum=sum+combi(v[0],v[b]);
}
p[a]=sum;
a++;
sum=0;
l=1;
break;
}
}
}
}
}
}
for(i=0;i<t;i++)
{
printf("%d\t ",p[i]);
}
printf("\n");
}
int combi(int x,int y)
{
int a=fact(x)/(fact(x-y)*fact(y));
return a;
}
long fact(int z)
{
int i=1;
long f=1;
while(i<=z)
{
f=f*i;
i++;
}
return f;
}