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class Solution {
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  public int[] simplifyEqn(String eqn) {
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    int prevSign = 1;
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    int sumX = 0;
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    int sumNums = 0;
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    for (int i = 0; i < eqn.length(); ) {
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      int coEff = 0;
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      int j = i;
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      while (j < eqn.length() && Character.isDigit(eqn.charAt(j))) {
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        coEff = coEff * 10 + (eqn.charAt(j) - '0');
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        j++;
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      }
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      if (j < eqn.length() && eqn.charAt(j) == 'x') {
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        if (i == j) coEff = 1;
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        sumX += prevSign * coEff;
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        j++;
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      } else {
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        sumNums += prevSign * coEff;
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      }
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      if (j < eqn.length() && eqn.charAt(j) == '+') prevSign = 1;
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      else if (j < eqn.length() && eqn.charAt(j) == '-') prevSign = -1;
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      i = ++j;
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    }
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    return new int[] {sumX, sumNums};
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  }
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  public String solveEquation(String equation) {
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    String[] leftNRight = equation.split("=");
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    String left = leftNRight[0], right = leftNRight[1];
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    int[] leftEqn = simplifyEqn(left);
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    int[] rightEqn = simplifyEqn(right);
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    int x = leftEqn[0] - rightEqn[0];
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    int num = rightEqn[1] - leftEqn[1];
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    if (x == 0)
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      if (num == 0) return "Infinite solutions";
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      else return "No solution";
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    return "x=" + num / x;
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  }
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}