6_Yet_Another_Simple_Calculator/6_Yet_Another_Simple_Calculator.c

@@ -0,0 +1,58 @@
+#include <stdio.h>
+
+void out(double* number) {
+    printf("The result is %lf.", *number);
+}
+
+int main() {
+    // vars
+    double numOne = 0, numTwo = 0, numOut = 0;
+    char cancel, operation;
+
+    // main loop
+    do {
+        // input for calculation
+        printf("Please type in the first number: ");
+        scanf("%lf", &numOne);
+        fflush(stdin);
+        printf("\nPlease type in the operation (+/-/*/:): ");
+        scanf("%c", &operation);
+        fflush(stdin);
+        printf("Please type in the second number: ");
+        scanf("%lf", &numTwo);
+        fflush(stdin);
+
+        // calculations
+        switch (operation) {
+            case '+':   // add
+                numOut = numOne + numTwo;
+                out(&numOut);
+                break;
+            case '-':   // subtract
+                numOut = numOne - numTwo;
+                out(&numOut);
+                break;
+            case '*':   // multiply
+                numOut = numOne * numTwo;
+                out(&numOut);
+                break;
+            case ':':   // divide
+                if (numTwo != 0) {
+                    numOut = numOne / numTwo;
+                    out(&numOut);
+                } else {
+                    printf("\nSecond number can't be 0.");
+                }
+                break;
+            default:    // other -> invalid operation
+                printf("\nInvalid operation.");
+        }
+        
+        // input 'q' if programm should be exited
+        printf("\nWould you like to enter another calculation? (any other key = continue, q = quit): ");
+        scanf("%c", &cancel);
+        fflush(stdin);
+    } while (cancel != 'q');    // end of do-while-loop
+
+    return 0;
+}

7_Matrix_1x1/7_Matrix_1x1.c

@@ -0,0 +1,16 @@
+#include <stdio.h>
+
+int main() {
+    // setting the end of the array
+    int upTo = 20;
+
+    // printing the values as matrix
+    for (int i = 1; i <= upTo; i++) {       // y axis
+        for (int j = 1; j <= upTo; j++) {   // x axis
+            printf("%5i", (i*j));           // printing each value, i*j = the value
+        }
+        printf("\n");                       // end of line on x axis
+    }
+
+    return 0;
+}