20221216/main.c

+#include <stdio.h>
+
+#define ROWS(a) (sizeof(a) / sizeof(a[0]))
+#define COLS(a) (sizeof(a[0]) / sizeof(a[0][0]))
+
+void input(int rows, int cols, int matrix[][cols]) {
+    for (int i = 0; i < rows; ++i) {
+        for (int j = 0; j < cols; ++j) {
+            printf("[%d][%d]: ", i, j);
+            scanf("%d", &matrix[i][j]);
+        }
+    }
+}
+
+int count_eq(int rows, int cols, int matrix[][cols], int key) {
+    int ret = 0;
+    for (int i = 0; i < rows; ++i) {
+        for (int j = 0; j < cols; ++j) {
+            if (matrix[i][j] == key) {
+                ++ret;
+            }
+        }
+    }
+    return ret;
+}
+
+int sum(
+        int rows1, int cols1, int a1[][cols1],
+        int rows2, int cols2, int a2[][cols2],
+        int rows3, int cols3, int a3[][cols3]) 
+{
+    int ret;
+    if (rows1 == rows2 && rows2 == rows3 && cols1 == cols2 && cols2 == cols3) {
+        int rows = rows1;
+        int cols = cols1;
+
+        for (int i = 0; i < rows; ++i) {
+            for (int j = 0; j < cols; ++j) {
+                a3[i][j] = a1[i][j] + a2[i][j];
+            }
+        }
+
+        ret = 0;
+    } else {
+        ret = -1;
+    }
+    return ret;
+}
+
+void print(int rows, int cols, int matrix[][cols]) {
+    for (int i = 0; i < rows; ++i) {
+        for (int j = 0; j < cols; ++j) {
+            printf("%3d ", matrix[i][j]);
+        }
+        puts("");
+    }
+}
+
+
+int multiply(
+        int rows1, int cols1, int a1[][cols1],
+        int rows2, int cols2, int a2[][cols2],
+        int rows3, int cols3, int a3[][cols3]) 
+{
+    int ret;
+    if (cols1 == rows2 && rows1 == rows3 && cols2 == cols3) {
+        for (int i = 0; i < rows1; ++i) {
+            for (int j = 0; j < cols2; ++j) {
+
+                int sum = 0;
+                for (int k = 0; k < rows2; ++k) {
+                    sum += a1[i][k] * a2[k][j];
+                }
+                a3[i][j] = sum;
+
+            }
+        }
+
+        ret = 1;
+    } else {
+        ret = -1;
+    }
+
+    return ret;
+}
+
+int main(void) {
+    int a1[2][3];
+    int a2[3][2];
+
+    puts("inserimento A");
+    input(ROWS(a1), COLS(a1), a1);
+    puts("inserimento B");
+    input(ROWS(a2), COLS(a2), a2);
+
+    int x;
+    printf("inserire x: ");
+    scanf("%d", &x);
+    printf("instanze di %d in A: %d\n", x, count_eq(ROWS(a1), COLS(a1), a1, x));
+
+    int y;
+    printf("inserire y: ");
+    scanf("%d", &y);
+    printf("instanze di %d in B: %d\n", y, count_eq(ROWS(a2), COLS(a2), a2, y));
+
+    int s[ROWS(a1)][COLS(a1)];
+    if (sum(ROWS(a1), COLS(a1), a1, ROWS(a2), COLS(a2), a2, ROWS(s), COLS(s), s) < 0) {
+        fputs("somma impossibile\n", stderr);
+    } else {
+        print(ROWS(s), COLS(s), s);
+    }
+
+    int m[2][2];
+    if (multiply(ROWS(a1), COLS(a1), a1, ROWS(a2), COLS(a2), a2, ROWS(m), COLS(m), m) < 0) {
+        fputs("prodotto impossibile\n", stderr);
+    } else {
+        print(ROWS(m), COLS(m), m);
+    }
+}

20230113/1/1.txt

+aaaaaa

20230113/1/2.txt

+aaabca

20230113/1/main.c

+#include <stdio.h>
+
+#include <errno.h>
+#include <string.h>
+#define err(s) fprintf(stderr, s "%s\n", strerror(errno))
+
+#define F1_STR "1.txt"
+#define F2_STR "2.txt"
+
+int main(void) {
+    int ret = 0;
+    FILE *f1;
+    if ((f1 = fopen(F1_STR, "r"))) {
+
+        FILE *f2;
+        if ((f2 = fopen(F2_STR, "r"))) {
+
+            char c1;
+            char c2;
+            int diff = 0;
+            while (fscanf(f1, "%c", &c1) != EOF &&
+                   fscanf(f2, "%c", &c2) != EOF &&
+                   !diff) {
+                if (c1 != c2) {
+                    diff = 1;
+                    printf("file 1: %c, file2: %c\n", c1, c2);
+                }
+            }
+            
+            fclose(f2);
+
+        } else {
+            ret = 1;
+            err(F2_STR ": ");
+        }
+
+        fclose(f1);
+    } else {
+        ret = 1;
+        err(F1_STR ": ");
+    }
+
+    return ret;
+}

20230113/2/1.txt

+abcdefghijk

20230113/2/2.txt

+abbdefgjklk

20230113/2/main.c

+#include <stdio.h>
+
+#include <errno.h>
+#include <string.h>
+#define err(s) fprintf(stderr, s "%s\n", strerror(errno))
+
+#define F1_STR "1.txt"
+#define F2_STR "2.txt"
+#define FOUT_STR "out.txt"
+
+int main(void) {
+    int ret = 0;
+    FILE *f1;
+    if ((f1 = fopen(F1_STR, "r"))) {
+
+        FILE *f2;
+        if ((f2 = fopen(F2_STR, "r"))) {
+
+            FILE *fout;
+            if ((fout = fopen(FOUT_STR, "w"))) {
+
+                char c1;
+                char c2;
+                while (fscanf(f1, "%c", &c1) != EOF &&
+                       fscanf(f2, "%c", &c2) != EOF) {
+                    if (c1 != c2) {
+                        printf("file 1: %c, file2: %c\n", c1, c2);
+                        fprintf(fout, "%c%c\n", c1, c2);
+                    }
+                }
+                fclose(fout);
+
+            } else {
+                ret = 1;
+                err(FOUT_STR ": ");
+            }
+            fclose(f2);
+        } else {
+            ret = 1;
+            err(F2_STR ": ");
+        }
+        fclose(f1);
+    } else {
+        ret = 1;
+        err(F1_STR ": ");
+    }
+
+    return ret;
+}

20230113/2/out.txt

+cb
+hj
+ik
+jl

20230113/3/1.txt

+aaa bbb ccc ddd eee

20230113/3/2.txt

+aaa b ccc dd eeee

20230113/3/main.c

+#include <stdio.h>
+
+#include <errno.h>
+#include <string.h>
+#define err(s) fprintf(stderr, s "%s\n", strerror(errno))
+
+#define F1_STR "1.txt"
+#define F2_STR "2.txt"
+
+int main(void) {
+    int ret = 0;
+    FILE *f1;
+    if ((f1 = fopen(F1_STR, "r"))) {
+
+        FILE *f2;
+        if ((f2 = fopen(F2_STR, "r"))) {
+
+            char s1[128];
+            char s2[128];
+            while (fscanf(f1, "%s", s1) != EOF &&
+                   fscanf(f2, "%s", s2) != EOF) {
+                if (strcmp(s1, s2) != 0) {
+                    puts(s2);
+                }
+            }
+
+            fclose(f2);
+        } else {
+            ret = 1;
+            err(F2_STR ": ");
+        }
+        fclose(f1);
+    } else {
+        ret = 1;
+        err(F1_STR ": ");
+    }
+
+    return ret;
+}

20230119/in1.txt

+1
+2
+3
+4
+5
+6
+7
+8
+9
+-1

20230119/in2.txt

+1
+2
+3
+3
+3
+9
+8
+7
+6
+-1

20230119/main.c

+#include <stdio.h>
+
+#define ARR_SIZE(arr) (sizeof(arr) / sizeof(*arr))
+
+#define MARK -1
+
+int write_to_file(char *filename, int arr[]) {
+    int ret = 0;
+
+    FILE *file;
+    if ((file = fopen(filename, "w")) == NULL) {
+        ret = -1;
+    } else {
+        int i = 0;
+        while (arr[i] != MARK && arr[i + 1] != MARK) {
+            fprintf(file, "%d-", arr[i]);
+
+            ++i;
+        }
+        fprintf(file, "%d", arr[i]);
+
+        fclose(file);
+    }
+
+    return ret;
+}
+
+int read_from_file(char *filename, int arr[], int size) {
+    int ret;
+    FILE *file;
+    if ((file = fopen(filename, "r")) == NULL) {
+        ret = -1;
+    } else {
+        int i = 0;
+        int end = 0;
+        int buf;
+        while (i < size && !end) {
+            fscanf(file, "%d", &buf);
+            if (buf == MARK) {
+                end = 1;
+            } else {
+                arr[i] = buf;
+                ++i;
+            }
+        }
+        if (end) {
+            arr[i] = MARK;
+            ret = i;
+        } else {
+            arr[0] = MARK;
+            ret = -1;
+        }
+
+        fclose(file);
+    }
+
+    return ret;
+}
+
+void modify(int arr1[], int arr2[]) {
+    int i = 0;
+    while (arr1[i] != MARK && arr2[i] != MARK) {
+        int a = arr1[i];
+        int b = arr2[i];
+        if (a == b) {
+            arr1[i] = 0;
+        } else if (a < b) {
+            arr1[i] = b;
+        } else {
+            ++arr1[i];
+        }
+        ++i;
+    }
+}
+
+int main(void) {
+    int ret = 0;
+
+    int arr1[10];
+    if (read_from_file("in1.txt", arr1, ARR_SIZE(arr1)) < 0) {
+        ret = 1;
+    } else {
+        int arr2[10];
+
+        if (read_from_file("in2.txt", arr2, ARR_SIZE(arr2)) < 0) {
+            ret = 1;
+        } else {
+            modify(arr2, arr1);
+            write_to_file("out.txt", arr2);
+        }
+    }
+
+    return ret;
+}

20230119/out.txt

+0-0-0-4-5-10-9-8-9
\ No newline at end of file