#include <stdio.h>

int main()
{
    int column[4] = {1, 2, 2, 3};
    int loop[4];
    int total = 0;
    int j;


    for (loop[0] = 1; loop[0] <= column[0]; loop[0]++) {
        for (loop[1] = 1; loop[1] <= column[1]; loop[1]++) {
            for (loop[2] = 1; loop[2] <= column[2]; loop[2]++) {
                for (loop[3] = 1; loop[3] <= column[3]; loop[3]++) {
                    for (j = 0; j < 4; j++) {
                    printf("%d ", loop[j]);
                    }
                    printf("\n");
                    total++;
                }
            }
        }
    }
    printf("\nTotal count = %d\n", total);
    free(column);
    return 0;
}

#include <stdio.h>
#include <stdlib.h>

int main()
{
    int i;
    int num_columns;
    int *column;
    int *loop;
    char *outname = "test.c";
    FILE *outfile;

    /* here is where you would put the code to let the user
     * enter the number of columns and the count values for
     * each. For purposes of illustration, I'll just give them
     * some values.
     */

    /*~~~~~beginning of block that will eventually get user input~~~*/
    num_columns = 4;
    column = malloc(num_columns * sizeof(int));
    column[0] = 1;
    column[1] = 2;
    column[2] = 2;
    column[3] = 3;
    /*~~~~~~~~~~~~~~~~~~~~end of user input block~~~~~~~~~~~~~~~~~~~*/

    /* now generate the program */
    if ((outfile = fopen(outname, "w")) == NULL) {
        printf("Can't open %s for writing\n", outname);
        exit(1);
    }
    printf("Opened output file %s\n", outname);

    fprintf(outfile, "/* test.c */\n");
    fprintf(outfile, "#include <stdio.h>\n");
    fprintf(outfile, "int main() {\n");
    fprintf(outfile, "int column[%d] = {", num_columns);
    for (i = 0; i < num_columns; i++) {
        fprintf(outfile, "%d", column[i]);
        if (i < num_columns-1) {
            fprintf(outfile, ", ");
        }
        else {
            fprintf(outfile, "};\n");
        }
    }
    fprintf(outfile, "int loop[%d];\n", num_columns);
    fprintf(outfile, "int total = 0;\n");
    fprintf(outfile, "int j;\n");
    /* now comes the fun stuff of nested loops. I'll just do something
     * simple
     */
    fprintf(outfile, "printf(\"The 'Hello World' of program generators.\\n\");\n");

    fprintf(outfile, "return 0;\n}\n");

    return 0;
}

/* test.c */
#include <stdio.h>
int main() {
int column[4] = {1, 2, 2, 3};
int loop[4];
int total = 0;
int j;
printf("The 'Hello World' of program generators.\n");
return 0;
}

    int column[4] = {1, 2, 2, 3};
    int loop[4];
    int total = 0;
    int j;

   

    for (loop[0] = 1; loop[0] <= column[0]; loop[0]++) {
        for (loop[1] = 1; loop[1] <= column[1]; loop[1]++) {
            for (loop[2] = 1; loop[2] <= column[2]; loop[2]++) {
                for (loop[3] = 1; loop[3] <= column[3]; loop[3]++) {
                    for (j = 0; j < 4; j++) {
                    printf("%d ", loop[j]);
                    }
                    printf("\n");
                    total++;
                }
            }
        }
    }
    printf("\nTotal count = %d\n", total);
    free(column);

#include <iostream>
#include <vector>


using namespace std;
  
   
void fillrec(int *col_f, vector<int> lastroute_f, int i){
    
   if(i<lastroute_f.size()){
        for(col_f[i] = 1; col_f[i] <= lastroute_f[i]; col_f[i]++) {        
        fillrec(col_f,lastroute_f,++i);
        }
        
        }else{
             for (int j = 0; j < lastroute_f.size(); j++) {
                cout << col_f[j] << " ";
             }
             cout <<endl;                   
   }
 
}


int main()
{

 vector<int> lastroute;
 lastroute.push_back(1);
 lastroute.push_back(2);
 lastroute.push_back(2);
 lastroute.push_back(3);

 int col[lastroute.size()];

 fillrec(col,lastroute,0);
    
 system("PAUSE");
    
 return 0;
}

#include <stdio.h>

void showvals(int *arr, int *col, int place, int size);

int main()
{
#define N 4
    int col[N] = {1, 2, 2, 3};
    int vals[N];

    showvals(vals, col, 0, N);

    return 0;
}


/* 
 * shows values for everything to the right of "place"
 *
 * "place" is the current column. 
 *
 * Go through the range of the current column and for each
 * value, show everything to the right by calling showvals
 * recursively, using "place + 1"
 *
 * When "place" is the rightmost column, go through the
 * range of that column, using everything to the left of it
 *
 */
void showvals(int *vals, int *col, int place, int size)
{
    int i;
    int j;
    if (place == size-1) {
        for (j = 1; j <= col[size-1]; j++) {
            for (i = 0; i < size-1; i++) {
                printf("%d ", vals[i]);
            }
            printf("%d\n", j);
        }
        return;
    }
    else {
        for(vals[place] = 1; vals[place] <= col[place]; vals[place]++) {
            showvals(vals, col, place+1, size);
        }
    }

}

/* 
 * Just to show how to get output from
 * the "combinations program" into another
 * program.
 *
 * Actual command line to combinations would
 * include "N" and the vector or array of
 * column counts, or something like that
 */
#include <stdio.h>
#include <stdlib.h>

int main()
{
    FILE *comb;
    char inbuf[BUFSIZ];
    char *pipename = "./combinations";
    int combno = 0;

    comb = popen(pipename, "r");
    if (popen == NULL) {
        printf("Can't open pipe %s\n", pipename);
        exit(1);
    }
    while (fgets(inbuf, sizeof(inbuf), comb)) {
        printf("%2d: %s", ++combno, inbuf);
    }
    pclose(comb);
    return 0;
}


/* 
 * shows values for everything to the right of "place"
 *
 * "place" is the current column. 
 *
 * Go through the range of the current column and for each
 * value, show everything to the right by calling showvals
 * recursively, using "place + 1"
 *
 * When "place" is the rightmost column, go through the
 * range of that column, using everything to the left of it
 *
 */
void showvals(int *vals, int *col, int place, int size)
{
    int i;
    int j;
    if (place == size-1) {
        for (j = 1; j <= col[size-1]; j++) {
            for (i = 0; i < size-1; i++) {
                printf("%d ", vals[i]);
            }
            printf("%d\n", j);
        }
        return;
    }
    else {
        for(vals[place] = 1; vals[place] <= col[place]; vals[place]++) {
            showvals(vals, col, place+1, size);
        }
    }

}

#include <stdio.h>
#include <stdlib.h>

int main()
{
    void printvec(int *, int);
    void incvec(int *val, int *col, int n);
    int i;
    int *val;
    int number_of_words;

    /*~~~~~~~~user input stuff here~~~~~*/
#define N 4
    int column[N] = {1, 2, 2, 3};
    /*~~~~~~end of user input~~~~~~~~*/

    val = malloc(N * sizeof(int));
    if (column == NULL) {
        printf("There was a problem allocating %d bytes for column\n",
                N * sizeof(int));
        exit(1);
    }

    /* 
     * Calculate the number of "words" that we will generate
     * it's simply equal to the product of the number of values that
     * the "digits" in each column can take on
     */
    number_of_words = 1;
    for (i = 0; i < N; i++) {
        number_of_words *= column[i];
    }

    /*
     * Initialize the word to all 1
     */
    for (i = 0; i < N; i++) {
        val[i] = 1;
    }

    printf("Number of words that will be generated = %d\n", number_of_words);


    for (i = 0; i < number_of_words; i++) {
        printvec(val, N);
        incvec(val, column, N);
    }
    free(val);

    return 0;
}

void printvec(int *x, int n)
{
    int i;
    for (i = 0; i < n; i++) {
        printf("%d ", x[i]);
    }
    printf("\n");
}

/* 
 * Treat the individual elements as digits
 * Start at the rightmost.
 * If incrementing it makes it too large, then
 * set it back to its lowest value and
 * continue through the loop to the next one
 * to the left.
 * If incrementing a digit does not make it too
 * large, then we are through
 */
void incvec(int *val, int *col, int n)
{
    int i;
    for (i = n-1; i >= 0; i--) {
        if (++val[i] > col[i]) {
            val[i] = 1;
        }
        else {
            break;
        }
    }
}