Contest Python: USACO Bronze › Unit 1 — Reading the Input

Exercises: Unit 1 — Reading the Input

Each problem is a program that reads the whole input from stdin and prints the exact output (real contest style — no solve() wrapper): import sys; data = sys.stdin.read(), parse it, print the answer. Write each program in a .py file and run it with piped input, e.g. python my_solution.py < case.txt.

Exercise 1: Sum and Maximum

The first line is N. The second line contains N integers. Print their sum and maximum, separated by one space.

Constraints

  • 1 <= N <= 1000
  • Every value is between 0 and 10000.

Sample Input

3
4 9 2

Sample Output

15 9

How this is checked: Checked by running your program on 2 test inputs (1 sample, 1 hidden) and comparing its output word by word.

For parents and teachers: report a problem

Exercise 2: Above the Threshold

The first line contains N T. The second line contains N integers. Print how many of those integers are greater than T.

Constraints

  • 1 <= N <= 1000
  • 0 <= T <= 10000
  • Every value is between 0 and 10000.

Sample Input

5 6
2 9 6 10 4

Sample Output

2

How this is checked: Checked by running your program on 3 test inputs (1 sample, 2 hidden) and comparing its output word by word.

For parents and teachers: report a problem

Exercise 3: Per-Line Sums

The first line is K. Each of the next K lines begins with a count M, followed by M integers. Print one sum for each of those lines, separated by spaces and kept in the same order.

Constraints

  • 1 <= K <= 100
  • 1 <= M <= 100 on every list line
  • Every value is between 0 and 1000.

Sample Input

3
3 2 4 6
2 10 5
4 1 1 2 3

Sample Output

12 15 7

How this is checked: Checked by running your program on 2 test inputs (1 sample, 1 hidden) and comparing its output word by word.

For parents and teachers: report a problem

Exercise 4: Find the Target

The first line contains N T. The second line contains N integers. Scan the values with a loop. If T is present, print YES and the first 1-based position, separated by one space. Otherwise, print NO.

Constraints

  • 1 <= N <= 1000
  • Every value and T is between 0 and 10000.

Sample Input

5 8
3 8 4 8 1

Sample Output

YES 2

How this is checked: Checked by running your program on 4 test inputs (1 sample, 3 hidden) and comparing its output word by word.

Also check yourself

The automatic check cannot see these, so tick each one when your work does it.

For parents and teachers: report a problem

Exercise 5: Grid Row Sums

The first line contains R C. The next R lines each contain C integers. Build the grid as a list of lists. Print the sum of each row, separated by spaces.

Constraints

  • 1 <= R <= 100
  • 1 <= C <= 100
  • Every grid value is between 0 and 1000.

Sample Input

2 3
1 2 3
4 5 6

Sample Output

6 15

How this is checked: Checked by running your program on 2 test inputs (1 sample, 1 hidden) and comparing its output word by word.

Also check yourself

The automatic check cannot see these, so tick each one when your work does it.

For parents and teachers: report a problem

Exercise 6: Grid Column Sums

The first line contains R C. The next R lines each contain C integers. Build the grid as a list of lists. Print the sum of each column from left to right, separated by spaces.

Constraints

  • 1 <= R <= 100
  • 1 <= C <= 100
  • Every grid value is between 0 and 1000.

Sample Input

2 3
1 2 3
4 5 6

Sample Output

5 7 9

How this is checked: Checked by running your program on 2 test inputs (1 sample, 1 hidden) and comparing its output word by word.

Also check yourself

The automatic check cannot see these, so tick each one when your work does it.

For parents and teachers: report a problem

Exercise 7: Double Every Number

The first line is N. The second line contains N integers. Double each integer and print all doubled values in order, separated by single spaces. Build the output with a loop.

Constraints

  • 1 <= N <= 1000
  • Every value is between 0 and 10000.

Sample Input

4
3 1 5 2

Sample Output

6 2 10 4

How this is checked: Checked by running your program on 2 test inputs (1 sample, 1 hidden) and comparing its output word by word.

Also check yourself

The automatic check cannot see these, so tick each one when your work does it.

For parents and teachers: report a problem

Exercise 8: Echo the Chosen Name

  • Challenge

The header line contains K P: the number of names and a 1-based position. The next K lines each contain one name with no spaces. Print the name at position P.

Constraints

  • 1 <= K <= 1000
  • 1 <= P <= K
  • Each name contains only letters and has no spaces.

Sample Input

4 3
Ari
Bo
Chen
Dee

Sample Output

Chen

How this is checked: Checked by running your program on 2 test inputs (1 sample, 1 hidden) and comparing its output word by word.

For parents and teachers: report a problem

Exercise 9: Grid Border Sum

  • Challenge

The first line contains R C. The next R lines each contain C integers. Build the grid as a list of lists. Print the sum of the outer-ring values: the first row, last row, first column, and last column. Count each corner once.

Constraints

  • 2 <= R <= 100
  • 2 <= C <= 100
  • Every grid value is between 0 and 1000.

Sample Input

3 4
1 2 3 4
5 6 7 8
9 10 11 12

Sample Output

65

How this is checked: Checked by running your program on 2 test inputs (1 sample, 1 hidden) and comparing its output word by word.

Also check yourself

The automatic check cannot see these, so tick each one when your work does it.

For parents and teachers: report a problem

Back to Unit 1 — Reading the Input