Coin Change LeetCode solution in Java

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class Solution {
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  public int coinChange(int[] coins, int amount) {
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    int m = coins.length, n = amount;
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    int dp[][] = new int[m + 1][n + 1];
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    for (int j = 0; j <= n; j++) {
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      dp[0][j] = 0;
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    }
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    for (int i = 0; i <= m; i++) {
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      dp[i][0] = 0;
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    }
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    for (int i = 1; i <= m; i++) {
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      for (int j = 1; j <= n; j++) {
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        int t1 = Integer.MAX_VALUE;
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        if ((i - 1) == 0) {
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          if (j % coins[i - 1] == 0) {
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            dp[i][j] = j / coins[i - 1];
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          } else {
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            dp[i][j] = (int) 1e9;
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          }
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        } else {
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          int t2 = dp[i - 1][j];
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          if (coins[i - 1] <= j) {
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            t1 = dp[i][j - coins[i - 1]] + 1;
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          }
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          dp[i][j] = Math.min(t1, t2);
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        }
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      }
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    }
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    if (dp[m][n] >= 1e9) return -1;
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    else return dp[m][n];
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  }
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}