printf() does not showing full sentence

I'm doing my school assignment and stuck in showing results.

#include <stdio.h>
#include <ctype.h>


int main(int argc, char *argv[]) {
    /* Declare input variable */
    char sentence[200];     // array that large enough for an sentence
    int i;

    /* Print the prompt */
    printf("Enter a sentence:");
    scanf("%s", &sentence);

    /* Change all white space characters to a space */
    for(i = 0; sentence[i]; i++)
    {
        if(isspace(sentence[i]))    //isspace to convert space, \t, \n
            sentence[i] = ' ';
    }

    /* Remove multiple spaces */
    i = 0;

    while(sentence[i] != '\0')      // \0 = NULL byte -> 0x30, address
    {
        if(sentence[i] == ' ' && sentence[i+1] == ' ')      // if there is two space
        for(int j = i; sentence[j]; j++)
        {
            sentence[j] = sentence[j+1];                    // eliminate one space
        }
        else
          i++;
    }


    sentence[0] = toupper(sentence[0]);     // Capitilize the first character of the sentence
    for(i = 1; sentence[i]; i++)
    {
        sentence[i] = tolower(sentence[i]);
    }

    /* Display the Output */
    printf("%s\n", sentence);

    return 0;
}

I followed the direction, but the result shows like this: enter image description here

I tried to build and run the code after annotating middle part to see if the input is same as output. But it came out the same as in the picture. I don't think it's a problem with the middle part, but I don't know what the problem is.

You don't need an ampersand here:

scanf("%s", &sentence);

In fact, you cannot get the whole sentence with the help of a scanf function. You need functions like fgets here. For example:

fgets(sentence, sizeof sentence, stdin);

and your problem is solved.

A sample output:

Enter a sentence:this sentence has  a double  space 
This sentence has a double space