diff --git a/problems/0435.无重叠区间.md b/problems/0435.无重叠区间.md
index 118360bc..389443d1 100644
--- a/problems/0435.无重叠区间.md
+++ b/problems/0435.无重叠区间.md
@@ -183,28 +183,22 @@ public:
 ```java
 class Solution {
     public int eraseOverlapIntervals(int[][] intervals) {
-        if (intervals.length < 2) return 0;
-
-        Arrays.sort(intervals, new Comparator<int[]>() {
-            @Override
-            public int compare(int[] o1, int[] o2) {
-                if (o1[1] != o2[1]) {
-                    return Integer.compare(o1[1],o2[1]);
-                } else {
-                    return Integer.compare(o1[0],o2[0]);
-                }
-            }
+        Arrays.sort(intervals, (a, b) -> {
+            if (a[0] == a[0]) return a[1] - b[1];
+            return a[0] - b[0];
         });
 
-        int count = 1;
-        int edge = intervals[0][1];
-        for (int i = 1; i < intervals.length; i++) {
-            if (edge <= intervals[i][0]){
-                count ++; //non overlap + 1
+        int count = 0;
+        int edge = Integer.MIN_VALUE;
+        for (int i = 0; i < intervals.length; i++) {
+            if (edge <= intervals[i][0]) {
                 edge = intervals[i][1];
+            } else {
+                count++;
             }
         }
-        return intervals.length - count;
+
+        return count;
     }
 }
 ```
diff --git a/problems/背包问题理论基础完全背包.md b/problems/背包问题理论基础完全背包.md
index f79310b8..cea69c72 100644
--- a/problems/背包问题理论基础完全背包.md
+++ b/problems/背包问题理论基础完全背包.md
@@ -183,11 +183,9 @@ private static void testCompletePack(){
     int[] value = {15, 20, 30};
     int bagWeight = 4;
     int[] dp = new int[bagWeight + 1];
-    for (int i = 0; i < weight.length; i++){
-        for (int j = 1; j <= bagWeight; j++){
-            if (j - weight[i] >= 0){
-                dp[j] = Math.max(dp[j], dp[j - weight[i]] + value[i]);
-            }
+    for (int i = 0; i < weight.length; i++){ // 遍历物品
+        for (int j = weight[i]; j <= bagWeight; j++){ // 遍历背包容量
+            dp[j] = Math.max(dp[j], dp[j - weight[i]] + value[i]);
         }
     }
     for (int maxValue : dp){
@@ -201,8 +199,8 @@ private static void testCompletePackAnotherWay(){
     int[] value = {15, 20, 30};
     int bagWeight = 4;
     int[] dp = new int[bagWeight + 1];
-    for (int i = 1; i <= bagWeight; i++){
-        for (int j = 0; j < weight.length; j++){
+    for (int i = 1; i <= bagWeight; i++){ // 遍历背包容量
+        for (int j = 0; j < weight.length; j++){ // 遍历物品
             if (i - weight[j] >= 0){
                 dp[i] = Math.max(dp[i], dp[i - weight[j]] + value[j]);
             }