Test results - Codility

Tasks Details

easy

1. TapeEquilibrium

Minimize the value |(A[0] + ... + A[P-1]) - (A[P] + ... + A[N-1])|.

Task Score

100%

Correctness

100%

Performance

100%

A non-empty array A consisting of N integers is given. Array A represents numbers on a tape.

Any integer P, such that 0 < P < N, splits this tape into two non-empty parts: A[0], A[1], ..., A[P − 1] and A[P], A[P + 1], ..., A[N − 1].

The difference between the two parts is the value of: |(A[0] + A[1] + ... + A[P − 1]) − (A[P] + A[P + 1] + ... + A[N − 1])|

In other words, it is the absolute difference between the sum of the first part and the sum of the second part.

For example, consider array A such that:

A[0] = 3 A[1] = 1 A[2] = 2 A[3] = 4 A[4] = 3

We can split this tape in four places:

P = 1, difference = |3 − 10| = 7

P = 2, difference = |4 − 9| = 5

P = 3, difference = |6 − 7| = 1

P = 4, difference = |10 − 3| = 7

Write a function:

int solution(vector<int> &A);

that, given a non-empty array A of N integers, returns the minimal difference that can be achieved.

For example, given:

A[0] = 3 A[1] = 1 A[2] = 2 A[3] = 4 A[4] = 3

the function should return 1, as explained above.

Write an efficient algorithm for the following assumptions:

N is an integer within the range [2..100,000];

each element of array A is an integer within the range [−1,000..1,000].

Solution

Programming language used C++

Time spent on task 9 minutes

Notes

not defined yet

Code: 09:34:23 UTC, java, autosave

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// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");

class Solution {
    public int solution(int[] A) {
        // write your code in Java SE 8
    }
}

Code: 09:34:28 UTC, cpp, autosave

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// you can use includes, for example:
// #include <algorithm>

// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
}

Code: 09:35:22 UTC, cpp, autosave

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1 2 3 4 5 6 7 8 9 10

// you can use includes, for example:
// #include <algorithm>

// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    
}

Code: 09:35:52 UTC, cpp, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13

// you can use includes, for example:
// #include <algorithm>

// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) conti
        A[i] += A[i-1];
    }
}

Code: 09:36:02 UTC, cpp, autosave

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1 2 3 4 5 6 7 8 9 10 11 12 13 14

// you can use includes, for example:
// #include <algorithm>

// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    
}

Code: 09:36:23 UTC, cpp, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19

// you can use includes, for example:
// #include <algorithm>

// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    for () {
        
        ans = min(ans, );
    }
    return ans;
}

Code: 09:36:53 UTC, cpp, autosave

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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

// you can use includes, for example:
// #include <algorithm>

// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    for (int i = 0; i < A.size(); i++) {
        int l = A[i] - A[0];
        int r = A[A.size() - 1] - A[]
        ans = min(ans, );
    }
    return ans;
}

Code: 09:36:59 UTC, cpp, verify, result: Failed

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// you can use includes, for example:
// #include <algorithm>

// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    for (int i = 0; i < A.size(); i++) {
        int l = A[i] - A[0];
        int r = A[A.size() - 1] - A[i];
        ans = min(ans, r-l);
    }
    return ans;
}

Analysis

Compile error

func.cpp: In function 'int solution(std::vector<int>&)':
func.cpp:9:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < A.size(); i++) {
                     ~~^~~~~~~~~~
func.cpp:13:15: error: 'INT_MAX' was not declared in this scope
     int ans = INT_MAX;
               ^~~~~~~
func.cpp:14:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < A.size(); i++) {
                     ~~^~~~~~~~~~

Code: 09:37:14 UTC, cpp, verify, result: Failed

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// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    for (int i = 0; i < A.size(); i++) {
        int l = A[i] - A[0];
        int r = A[A.size() - 1] - A[i];
        ans = min(ans, r-l);
    }
    return ans;
}

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got -10 expected 1

0.001 s

WRONG ANSWER, got -10 expected 1

Code: 09:37:50 UTC, cpp, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    for (int i = 1; i < A.size(); i++) {
        int l = A[i] - A[0];
        int r = A[A.size() - 1] - A[i];
        ans = min(ans, r-l);
    }
    return ans;
}

Code: 09:37:52 UTC, cpp, verify, result: Failed

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    for (int i = 1; i < A.size(); i++) {
        int l = A[i] - A[0];
        int r = A[A.size() - 1] - A[i];
        ans = min(ans, r-l);
    }
    return ans;
}

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got -10 expected 1

0.001 s

WRONG ANSWER, got -10 expected 1

Code: 09:38:31 UTC, cpp, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    A[]
    for (int i = 1; i < A.size(); i++) {
        int l = A[i] - A[0];
        int r = A[A.size() - 1] - A[i];
        ans = min(ans, r-l);
    }
    return ans;
}

Code: 09:38:41 UTC, cpp, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    A[0] = 0;
    for (int i = 1; i < A.size(); i++) {
        int l = A[i] - A[0];
        int r = A[A.size() - 1] - A[i];
        ans = min(ans, r-l);
    }
    return ans;
}

Code: 09:38:57 UTC, cpp, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    
    for (int i = 1; i < A.size(); i++) {
        int l = A[i] - A[0];
        int r = A[A.size() - 1] - A[i];
        ans = min(ans, r-l);
    }
    return ans;
}

Code: 09:39:23 UTC, cpp, verify, result: Failed

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    
    for (int i = 1; i < A.size(); i++) {
        int l = A[i] - A[0];
        int r = A[A.size() - 1] - A[i];
        cout << i << " " << l << " " << r << endl;
        ans = min(ans, r-l);
    }
    return ans;
}

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got -10 expected 1

0.001 s

WRONG ANSWER, got -10 expected 1

stdout:

Code: 09:40:19 UTC, cpp, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    
    for (int i = 1; i < A.size(); i++) {
        int l = A[i] - A[0];
        int r = A[A.size() - 1] - A[i-];
        cout << i << " " << l << " " << r << endl;
        ans = min(ans, r-l);
    }
    return ans;
}

Code: 09:40:21 UTC, cpp, verify, result: Failed

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    
    for (int i = 1; i < A.size(); i++) {
        int l = A[i] - A[0];
        int r = A[A.size() - 1] - A[i-1];
        cout << i << " " << l << " " << r << endl;
        ans = min(ans, r-l);
    }
    return ans;
}

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got -7 expected 1

0.001 s

WRONG ANSWER, got -7 expected 1

stdout:

Code: 09:41:29 UTC, cpp, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    
    for (int i = 1; i < A.size(); i++) {
        int l = A[i];
        int r = A[A.size() - 1] - A[i-1];
        cout << i << " " << l << " " << r << endl;
        ans = min(ans, r-l);
    }
    return ans;
}

Code: 09:41:31 UTC, cpp, verify, result: Failed

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    
    for (int i = 1; i < A.size(); i++) {
        int l = A[i];
        int r = A[A.size() - 1] - A[i-1];
        cout << i << " " << l << " " << r << endl;
        ans = min(ans, r-l);
    }
    return ans;
}

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got -10 expected 1

0.001 s

WRONG ANSWER, got -10 expected 1

stdout:

Code: 09:41:40 UTC, cpp, verify, result: Failed

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    
    for (int i = 1; i < A.size(); i++) {
        int l = A[i-1];
        int r = A[A.size() - 1] - A[i-1];
        cout << i << " " << l << " " << r << endl;
        ans = min(ans, r-l);
    }
    return ans;
}

Analysis

expand all Example tests

▶

example
example test

✘

WRONG ANSWER
got -7 expected 1

0.001 s

WRONG ANSWER, got -7 expected 1

stdout:

Code: 09:41:57 UTC, cpp, verify, result: Passed

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    
    for (int i = 1; i < A.size(); i++) {
        int l = A[i-1];
        int r = A[A.size() - 1] - A[i-1];
        cout << i << " " << l << " " << r << endl;
        ans = min(ans, abs(r-l));
    }
    return ans;
}

Analysis

expand all Example tests

▶

example
example test

✔

0.001 s

stdout:

Code: 09:42:12 UTC, cpp, autosave

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    
    for (int i = 1; i < A.size(); i++) {
        int l = A[i-1];
        int r = A[A.size() - 1] - A[i-1];
        ans = min(ans, abs(r-l));
    }
    return ans;
}

Code: 09:42:14 UTC, cpp, verify, result: Passed

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    
    for (int i = 1; i < A.size(); i++) {
        int l = A[i-1];
        int r = A[A.size() - 1] - A[i-1];
        ans = min(ans, abs(r-l));
    }
    return ans;
}

Analysis

expand all Example tests

▶

example
example test

✔

0.001 s

Code: 09:42:22 UTC, cpp, verify, result: Passed

show code in pop-up

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    
    for (int i = 1; i < A.size(); i++) {
        int l = A[i-1];
        int r = A[A.size() - 1] - A[i-1];
        ans = min(ans, abs(r-l));
    }
    return ans;
}

Analysis

expand all Example tests

▶

example
example test

✔

0.001 s

Code: 09:42:25 UTC, cpp, final, score: 100

show code in pop-up

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// you can use includes, for example:
// #include <algorithm>
#include <climits>
// you can write to stdout for debugging purposes, e.g.
// cout << "this is a debug message" << endl;

int solution(vector<int> &A) {
    // write your code in C++14 (g++ 6.2.0)
    for (int i = 0; i < A.size(); i++) {
        if (i == 0) continue;
        A[i] += A[i-1];
    }
    int ans = INT_MAX;
    
    for (int i = 1; i < A.size(); i++) {
        int l = A[i-1];
        int r = A[A.size() - 1] - A[i-1];
        ans = min(ans, abs(r-l));
    }
    return ans;
}

Analysis summary

The solution obtained perfect score.

Analysis

Detected time complexity:

O(N)

expand all Example tests

▶

example
example test

✔

0.001 s

expand all Correctness tests

▶

double
two elements

✔

0.001 s

▶

simple_positive
simple test with positive numbers, length = 5

✔

0.001 s

▶

simple_negative
simple test with negative numbers, length = 5

✔

0.001 s

▶

simple_boundary
only one element on one of the sides

✔

0.001 s

▶

small_random
random small, length = 100

✔

0.001 s

▶

small_range
range sequence, length = ~1,000

✔

0.001 s

▶

small
small elements

✔

0.001 s

expand all Performance tests

▶

medium_random1
random medium, numbers from 0 to 100, length = ~10,000

✔

0.001 s

▶

medium_random2
random medium, numbers from -1,000 to 50, length = ~10,000

✔

0.001 s

▶

large_ones
large sequence, numbers from -1 to 1, length = ~100,000

✔

0.004 s

▶

large_random
random large, length = ~100,000

✔

0.004 s

▶

large_sequence
large sequence, length = ~100,000

✔

0.004 s

▶

large_extreme
large test with maximal and minimal values, length = ~100,000

✔

0.004 s

0.008 s

0.004 s