That's because your solution does not handle the specified kind of input. In input you have no numbers, the mountains are given literally as a map filled with ^. Look at the sampel tests, and the example input:

    char[][] mountain = {
      "^^^^^^        ".toCharArray(),
      " ^^^^^^^^     ".toCharArray(),
      "  ^^^^^^^     ".toCharArray(),
      "  ^^^^^       ".toCharArray(),
      "  ^^^^^^^^^^^ ".toCharArray(),
      "  ^^^^^^      ".toCharArray(),
      "  ^^^^        ".toCharArray()
    };      
    assertEquals(3, Dinglemouse.peakHeight(mountain));

Your solution should handle a map of mountains and deduce the numbers.

```java
public static int peakHeight(char[][] mountain) {
    int maxValue = Integer.MIN_VALUE;
    for(int i = 0;i<mountain.length;i++){
        for (int j = 0;j<mountain[i].length;j++) {
            char c = mountain[i][j];
            if (c != ' ' && c != '^') {
                Integer integer = Integer.parseInt(String.valueOf(c));
                if (maxValue < integer) {
                    maxValue = integer;
                }
            }
        }
    }
    return maxValue;
}


public static void main(String[] args) {
        char[][] mountain = {
                "111111        ".toCharArray(),
                " 12222111     ".toCharArray(),
                "  1233211     ".toCharArray(),
                "  12321       ".toCharArray(),
                "  12332111111 ".toCharArray(),
                "  122211      ".toCharArray(),
                "  1111        ".toCharArray()
        };
    System.out.println(peakHeight(mountain));
    }
}

We don't know. We would have to see your code to know.

when I solve a problem in an IDEA, and put the ^ numbers in place manually,
the solution turns out correctly,
it turns out 3, but when I run it in codewars the answer is -
expected:<3> but was:<-2147483648>
why?

BEST KATA EVER !!!!!!!!!!!!!!!!!

самое простое и понятное решение, именно такие должны быть в коде, сложные решения через стримы крутые, но они слишком замороченные и могут быть с ошибками

гениально