feat: add java solution to lc problem: No.3048 (doocs#2387)

No.3048.Earliest Second to Mark Indices I Co-authored-by: Libin YANG <[email protected]>
CodersAcademy006 · Mar 8, 2024 · 891dc6e · 891dc6e
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diff --git a/solution/3000-3099/3048.Earliest Second to Mark Indices I/README.md b/solution/3000-3099/3048.Earliest Second to Mark Indices I/README.md
@@ -91,7 +91,51 @@
 ```
 
 ```java
-
+class Solution {
+    public int earliestSecondToMarkIndices(int[] nums, int[] changeIndices) {
+        int l = 0;
+        int r = changeIndices.length + 1;
+        while (l < r) {
+            final int m = (l + r) / 2;
+            if (canMark(nums, changeIndices, m)) {
+                r = m;
+            } else {
+                l = m + 1;
+            }
+        }
+        return l <= changeIndices.length ? l : -1;
+    }
+
+    private boolean canMark(int[] nums, int[] changeIndices, int second) {
+        int numMarked = 0;
+        int decrement = 0;
+        // indexToLastSecond[i] := the last second to mark the index i
+        int[] indexToLastSecond = new int[nums.length];
+        Arrays.fill(indexToLastSecond, -1);
+
+        for (int i = 0; i < second; ++i) {
+            indexToLastSecond[changeIndices[i] - 1] = i;
+        }
+
+        for (int i = 0; i < second; ++i) {
+            // Convert to 0-indexed.
+            final int index = changeIndices[i] - 1;
+            if (i == indexToLastSecond[index]) {
+                // Reach the last occurrence of the number.
+                // So, the current second will be used to mark the index.
+                if (nums[index] > decrement) {
+                    // The decrement is less than the number to be marked.
+                    return false;
+                }
+                decrement -= nums[index];
+                ++numMarked;
+            } else {
+                ++decrement;
+            }
+        }
+        return numMarked == nums.length;
+    }
+}
 ```
 
 ```cpp

diff --git a/solution/3000-3099/3048.Earliest Second to Mark Indices I/README_EN.md b/solution/3000-3099/3048.Earliest Second to Mark Indices I/README_EN.md
@@ -87,7 +87,51 @@ Hence, the answer is -1.
 ```
 
 ```java
-
+class Solution {
+    public int earliestSecondToMarkIndices(int[] nums, int[] changeIndices) {
+        int l = 0;
+        int r = changeIndices.length + 1;
+        while (l < r) {
+            final int m = (l + r) / 2;
+            if (canMark(nums, changeIndices, m)) {
+                r = m;
+            } else {
+                l = m + 1;
+            }
+        }
+        return l <= changeIndices.length ? l : -1;
+    }
+
+    private boolean canMark(int[] nums, int[] changeIndices, int second) {
+        int numMarked = 0;
+        int decrement = 0;
+        // indexToLastSecond[i] := the last second to mark the index i
+        int[] indexToLastSecond = new int[nums.length];
+        Arrays.fill(indexToLastSecond, -1);
+
+        for (int i = 0; i < second; ++i) {
+            indexToLastSecond[changeIndices[i] - 1] = i;
+        }
+
+        for (int i = 0; i < second; ++i) {
+            // Convert to 0-indexed.
+            final int index = changeIndices[i] - 1;
+            if (i == indexToLastSecond[index]) {
+                // Reach the last occurrence of the number.
+                // So, the current second will be used to mark the index.
+                if (nums[index] > decrement) {
+                    // The decrement is less than the number to be marked.
+                    return false;
+                }
+                decrement -= nums[index];
+                ++numMarked;
+            } else {
+                ++decrement;
+            }
+        }
+        return numMarked == nums.length;
+    }
+}
 ```
 
 ```cpp

diff --git a/solution/3000-3099/3048.Earliest Second to Mark Indices I/Solution.java b/solution/3000-3099/3048.Earliest Second to Mark Indices I/Solution.java
@@ -0,0 +1,45 @@
+class Solution {
+    public int earliestSecondToMarkIndices(int[] nums, int[] changeIndices) {
+        int l = 0;
+        int r = changeIndices.length + 1;
+        while (l < r) {
+            final int m = (l + r) / 2;
+            if (canMark(nums, changeIndices, m)) {
+                r = m;
+            } else {
+                l = m + 1;
+            }
+        }
+        return l <= changeIndices.length ? l : -1;
+    }
+
+    private boolean canMark(int[] nums, int[] changeIndices, int second) {
+        int numMarked = 0;
+        int decrement = 0;
+        // indexToLastSecond[i] := the last second to mark the index i
+        int[] indexToLastSecond = new int[nums.length];
+        Arrays.fill(indexToLastSecond, -1);
+
+        for (int i = 0; i < second; ++i) {
+            indexToLastSecond[changeIndices[i] - 1] = i;
+        }
+
+        for (int i = 0; i < second; ++i) {
+            // Convert to 0-indexed.
+            final int index = changeIndices[i] - 1;
+            if (i == indexToLastSecond[index]) {
+                // Reach the last occurrence of the number.
+                // So, the current second will be used to mark the index.
+                if (nums[index] > decrement) {
+                    // The decrement is less than the number to be marked.
+                    return false;
+                }
+                decrement -= nums[index];
+                ++numMarked;
+            } else {
+                ++decrement;
+            }
+        }
+        return numMarked == nums.length;
+    }
+}