PASS Week 9 Solutions

PROBLEM #1 SOLUTION

#include <stdio.h>

int main(){

    int a[5];
    int b[5];

    for(int i = 0; i < 5; i++){
        a[i] = i + 1; //Fill A with values
    }

    printf("A: ");
    for(int i = 0; i < 5; i++){
        printf("%d ", a[i]); //Print A
    }

    printf("\n");

    for(int i = 0; i < 5; i++){
        b[i] = a[4-i]; //Fill B with A's values but backwards
    }

    printf("B: ");
    for(int i = 0; i < 5; i++){
        printf("%d ", b[i]); //Print B
    }

    printf("\n");

    return 0;
}














PROBLEM #2 SOLUTION

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

int main(){

    char fName[20] = "";
    char lName[20] = "";
    char ssn[5] = "";
    char userID[20] = "";

    printf("Enter in your first name: ");
    scanf("%s", fName);
    printf("Enter in your last name: ");
    scanf("%s", lName);
    printf("Enter in the last 4 digits of your SSN: ");
    scanf("%s", ssn);

    userID[0] = lName[0];
    userID[1] = lName[1];
    userID[2] = lName[2];
    userID[3] = fName[0];
    userID[4] = fName[1];
    userID[5] = ssn[0];
    userID[6] = ssn[1];
    userID[7] = ssn[2];
    userID[8] = ssn[3];

    printf("\nUnique User ID is %s\n", userID);

    return 0;
}














PROBLEM #3 SOLUTION

#include <stdio.h>

int main(){

    int ary[10];
    int temp = 0;

    for(int i = 0; i < 10; i++){
        ary[i] = i + 1; //Fill ary with values
    }

    printf("Array before reversing: ");
    for(int i = 0; i < 10; i++){
        printf("%d ", ary[i]); //Print ary
    }

    printf("\n");
    for (int i = 0; i < 5; i++){
        temp = ary[i];
        ary[i] = ary[9 - i];
        ary[9 - i] = temp;
    }

    printf("Array after reversing: ");
    for(int i = 0; i < 10; i++){
        printf("%d ", ary[i]); //Print ary
    }
    printf("\n");

    return 0;
}











PROBLEM #4 SOLUTION

#include <stdio.h>

int main(){

    int isbn[10];
    int sum = 0;
    int countdown = 10;

    for(int i = 0; i < 10; i++){
        printf("Enter in 10 numbers one at a time: ");
        scanf("%d", &isbn[i]);
    }

    for(int i = 0; i < 10; i++){
        sum += (isbn[i] * countdown--);
    }

	printf("Weighted Sum is: %d\n", sum);
    if (sum % 11 == 0){
        printf("The ISBN is valid\n");
    }
    else{
        printf("The ISBN is invalid\n");
    }

    return 0;
}