填充温度频率数组遇多频次数据中断问题求助

Your problem boils down to a key misstep: you’re using the raw temp array (which has duplicate entries for temperatures with frequency >1) to match against your continuous temperature range, instead of leaning on the HashMap you already built that holds exact frequency counts.

Why Your Current Code Fails #

Let’s walk through the issue with your 14°C example:

• When your loop reaches the index for 14°C, it matches temp[j] (which is 14), sets finalTemps[i] to 2, and increments j.
• Now temp[j] is still 14 (since your raw temp array has two entries for 14), but the next tempGaps[i] is 15. These don’t match, so you set finalTemps[i] to 0 and keep incrementing j.
• Eventually, j will run past the end of the temp array, and every subsequent tempGaps[i] will fail to match, leaving all remaining finalTemps values as 0.

The Fix: Use Your HashMap Directly #

Since you already have a HashMap that maps each temperature to its frequency, you don’t need to touch the raw temp array at all. Here’s the corrected fillGaps method:

public void fillGaps() {
    // Critical fix: The number of continuous temps is (max - min + 1), not just difference
    int totalTemps = difference + 1;
    tempGaps = new int[totalTemps];
    finalTemps = new int[totalTemps];
    
    int minTemp = temp[0]; // Assuming temp is sorted, or you have a precomputed min temp
    for (int i = 0; i < totalTemps; i++) {
        int currentTemp = minTemp + i;
        tempGaps[i] = currentTemp;
        // Use getOrDefault to safely get frequency, defaulting to 0 if temp isn't present
        finalTemps[i] = map.getOrDefault(currentTemp, 0);
    }
}

Key Improvements #

• Ditched the j pointer and temp array dependency: Your HashMap is the single source of truth for frequencies—no need to iterate through raw data that has duplicates.
• Fixed array length: Your original difference is maxTemp - minTemp, so the number of continuous temperatures is difference + 1 (e.g., 7 to 21 is 15 values, 21-7=14, 14+1=15). This prevents missing the highest temperature.
• Simplified frequency lookup: HashMap.getOrDefault() handles both existing and missing temperatures in one line, no conditional checks needed.

Expected Result #

With this fix, your finalTemps array will populate correctly:

• For 14°C, it pulls the value 2 directly from the map
• Subsequent temperatures like 15, 16, 18 will get their correct frequencies instead of 0
• Missing temperatures (like 8, 11) will still show 0 as expected

内容的提问来源于stack exchange，提问作者ricemvm