C++ Programming Code Examples
C++ > Algorithms Code Examples
Word Frequency
/* Word Frequency */
#include <stdio.h>
#define SIZE 80
#define LEN 80
int strword(char[],char[][]);
int strword_p(char*,char**);
void main(){
char* s;
char** w;
char ch;
do{
clrscr();
gotoxy(10,1);
printf("Enter a string :");
gets(s);
gotoxy(10,2);
printf("\nNumber of words :%d",strword_p(s,w));
gotoxy(10,24);
printf(" Continue(y/n)?");
ch=getch();
} while (ch=='y' || ch=='Y');
}
int strword_p(char *s,char **w){
int is_space=0,
i=0,
word_counter=0,
j=0,
is_printed=0,
frequency=0;
while (*(s+i)!='\0'){
if (*(s+i)==' ' ||
*(s+i)==',' ||
*(s+i)=='.' ||
*(s+i)==':'){
if (is_space==0){
*(*(w+word_counter)+j)='\0';
word_counter++;
is_space=1;
j=0;
}
}
else{
*(*(w+word_counter)+j)=*(s+i);
j++;
is_space=0;
}
i++;
}
if (is_space==0){
*(*(w+word_counter)+j)='\0';
word_counter++;
}
for(j=0;j<word_counter;j++){
frequency=0;
is_printed=0;
for(i=0;i<word_counter;i++){
if (strcmp(w[i],w[j])==0){
frequency++;
if (j<i)
is_printed=1;
}
}
if (!is_printed)
printf("\n Word %d : %s ,frequency->%d",j+1,w[j],frequency);
}
printf("\n");
return word_counter;
}
It is a predefined function in "conio.h" (console input output header file) used to clear the console screen. It is a predefined function, by using this function we can clear the data from console (Monitor). Using of clrscr() is always optional but it should be place after variable or function declaration only. It is often used at the beginning of the program (mostly after variable declaration but not necessarily) so that the console is clear for our output.
The getch() is a predefined non-standard function that is defined in conio.h header file. It is mostly used by the Dev C/C++, MS- DOS's compilers like Turbo C to hold the screen until the user passes a single value to exit from the console screen. It can also be used to read a single byte character or string from the keyboard and then print. It does not hold any parameters. It has no buffer area to store the input character in a program. The getch() function does not accept any parameter from the user. It returns the ASCII value of the key pressed by the user as an input.
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Get string from stdin. Reads characters from the standard input (stdin) and stores them as a C string into str until a newline character or the end-of-file is reached. The newline character, if found, is not copied into str. A terminating null character is automatically appended after the characters copied to str. Notice that gets is quite different from fgets: not only gets uses stdin as source, but it does not include the ending newline character in the resulting string and does not allow to specify a maximum size for str (which can lead to buffer overflows). On success, the function returns str.
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In computer programming, loops are used to repeat a block of code. For example, when you are displaying number from 1 to 100 you may want set the value of a variable to 1 and display it 100 times, increasing its value by 1 on each loop iteration. When you know exactly how many times you want to loop through a block of code, use the for loop instead of a while loop. A for loop is a repetition control structure that allows you to efficiently write a loop that needs to execute a specific number of times.
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In while loop, condition is evaluated first and if it returns true then the statements inside while loop execute, this happens repeatedly until the condition returns false. When condition returns false, the control comes out of loop and jumps to the next statement in the program after while loop. The important point to note when using while loop is that we need to use increment or decrement statement inside while loop so that the loop variable gets changed on each iteration, and at some point condition returns false. This way we can end the execution of while loop otherwise the loop would execute indefinitely. A while loop that never stops is said to be the infinite while loop, when we give the condition in such a way so that it never returns false, then the loops becomes infinite and repeats itself indefinitely.
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Positions cursor in text window. The gotoxy() function places the cursor at the desired location on the screen. This means it is possible to change the cursor location on the screen using the gotoxy() function. It is basically used to print text wherever the cursor is moved. If the coordinates are in any way invalid the call to gotoxy is ignored. Neither argument to gotoxy can be zero.
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Program sample takes the values of two large numbers as input and displays the computed value node with node in the resultant Linked List. Result of "subtraction" for two numbers
