Printing square using specified character and multiplying chars-CodePudding

Write a programme that prints a square pattern of side length M of any single character specified by the user using a single for loop and a single if else statement. You should define both M and the character constant C as preprocessor statements.

I actually did that but I wonder is there any easier way to solve this problem. Here's my code:

#include <stdio.h>
#include <string.h>

int
main()
{

    int M, i = 1;
    char C, G[1000];

    printf("Input a value for side length:\n");
    scanf("%d", &M);

    printf("Input a character for pattern:\n");
    scanf(" %c", &C);

    for (; i <= M; i  ) {
        printf("%c", C);

        if (i <= M) {
            memset(G, C, (M - 1));
            G[M - 1] = '\0';
            puts(G);
        }

    }

    return 0;
}

CodePudding user response：

Something along these lines, perhaps:

int M1 = M   1;
for (int i = 0; i < M*M1;   i) {
  if (i % M1 == M) putchar('\n');
  else putchar(C);
}

CodePudding user response：

How about this:

#include <stdio.h>

int main(int argc, char *argv[])
{

    int M, i, j;
    char C;

    /* Enter both parameters and validate input */
    do {
        printf("Input side length, char for pattern: ");
    } while (scanf("%d %c", &M, &C) != 2);

    /* Draw the square */
    for (i=0; i < M; i  ) {
        for (j=0; j< M; j  ) {
            printf("%c", C);
        }
        printf ("\n");
    }

    /* Done */
    return 0;
}

Or better, break your app into separate functions:

#include <stdio.h>

void get_parameters(int *length, char *c)
{
    do {
        printf("Input side length, char for pattern: ");
    } while (scanf("%d %c", length, c) != 2);
}

void draw_shape(int M, char C)
{
    int i, j;
    for (i=0; i < M; i  ) {
        for (j=0; j< M; j  ) {
            printf("%c", C);
        }
        printf ("\n");
    }
}

int main(int argc, char *argv[])
{
    int M;
    char C;

    get_parameters(&M, &C);
    draw_shape(M, C);
}

CodePudding user response：

You can do the memset outside of the loop once.

You can just do puts inside the loop:

#include <stdio.h>
#include <string.h>

int
main()
{

    int M, i = 1;
    char C, G[1000];

    printf("Input a value for side length:\n");
    scanf("%d", &M);

    printf("Input a character for pattern:\n");
    scanf(" %c", &C);

    memset(G, C, M);
    G[M] = '\0';

    for (; i <= M; i  )
        puts(G);

    return 0;
}

For an input of 8 rows and a char of *, the output is:

Input a value for side length:
8
Input a character for pattern:
*
********
********
********
********
********
********
********
********

UPDATE:

After rereading the requirements, if C and M must be macros, the code should be:

#include <stdio.h>
#include <string.h>

#ifndef M
#error M not defined
#endif

#ifndef C
#error C not defined
#endif

int
main()
{

    int i = 1;
    char G[1000];

    memset(G, C, M);
    G[M] = '\0';

    for (; i <= M; i  )
        puts(G);

    return 0;
}

And, the program should be compiled with:

cc -o program -DM=8 -DC="'*'" program.c