pangram function is not working in c - c

Question

#include<stdio.h>
#include<ctype.h>
#include<stdbool.h>
#include<string.h>
#define number_of_letters 26
bool IsPangram(char* string);
int main(){
char check[100];
when i put the output as "the quick brown fox jumps over the lazy dog" the output is no a pangram
and when i put a to z values on one single line is gives the correct output
scanf("%s",&check);
if(IsPangram(check)){
printf("the string entered is pangram");
}
else{
printf("not a pangram");
}
return 0;
}
there is the function for pangram
bool IsPangram(char* string){
bool flags[number_of_letters];
int size=strlen(string);
bool ispangram=true;
int i;
char c;
// for all the alfabets to be setting them to false
for(i=0;i<number_of_letters;i++){
flags[i]=false;
}
// for converting the uppper case letter to the small one
for(i=0;i<size;i++){
c=tolower(string[i]);
if(islower(c)){
flags[string[i]-'a']=true;
}
}
// for checking the the lettters to no pangram
for(i=0;(i<number_of_letters && ispangram==true);i++){
if(flags[i]==false){
ispangram=false;
}
}
return ispangram;
}

Answer 1

You don't need use & when passing a string as a char *, since arrays decay to pointers when passed as parameters.
So:
scanf("%s",&check);
should be:
scanf("%s", check);
And some general advice: turn on compiler warnings to help catch simple mistakes such as this, and learn basic debugging techniques (stepping through code in your debugger, adding strategic printf statements, etc).

Answer 2

scanf() with the %s format specifier will stop at whitespace. Try fgets(check,100,stdin) instead... that will read (up to) a full line, and limit the number of characters to 99 + nul so you won't exceed the size of check. It may leave a newline as the last character, but your algorithm would ignore that anyway.
Additionally, in IsPangram(), c should be an int instead of a char (to match tolower() etc.), and change this:
// for converting the uppper case letter to the small one
for(i=0;i<size;i++){
c=tolower(string[i]);
if(islower(c)){
flags[string[i]-'a']=true;
}
}
...to this:
// for converting the uppper case letter to the small one
for(i=0;i<size;i++){
c=tolower(string[i]); /* <== c will always be lowercase */
if(isalpha(c)){ /* <== Check that c is a letter */
flags[c-'a']=true; /* <== use c, as string[i] may be uppercase */
}
}
...for the reasons indicated in the added comments.

Answer 3

scanf cannot get strings with spaces. So use fgets
fgets(check,sizeof(check),stdin);
Or use
scanf("%[^\n]s",check);
This reads a string till a newline character is encountered.
The default scanf stops reading when a space is encountered.

Answer 4

Here you go:
#include <ctype.h>
void uc(char*s){for(;*s;*s=toupper(*s),s++);}
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
int main(int argc,char*argv[])
{int i,j,n=0,c[256]={0};
char*s,*w[1024]={NULL};
do w[n]=malloc(1024),fgets(w[n],1024,stdin),w[n][strlen(w[n])-1]='\0',uc(w[n]),n++;
while(n<1024&&strlen(w[n-1]));
for(--n,i=0;i<n;++i)
for(j=0;j<strlen(w[i]);++j)
c[w[i][j]]=1;
for(j=0,i='A';i<='Z';++i)j+=c[i];
printf("It's %sa pangram\n",j==26?"":"not ");
for(i=0;i<=n;free(w[i++]));}