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			23 lines
		
	
	
		
			523 B
		
	
	
	
		
			Solidity
		
	
	
	
	
	
			
		
		
	
	
			23 lines
		
	
	
		
			523 B
		
	
	
	
		
			Solidity
		
	
	
	
	
	
| pragma experimental SMTChecker;
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| 
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| contract C
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| {
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| 	function f(uint x, bool b) public pure {
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| 		require(x < 100);
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| 		while (x < 10) {
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| 			if (b)
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| 				x = x + 1;
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| 			else
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| 				x = 0;
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| 		}
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| 		// CHC proves it safe because
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| 		// 1- if it doesn't go in the loop in the first place, x >= 10
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| 		// 2- if it goes in the loop and b == true, x increases until >= 10
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| 		// 3- if it goes in the loop and b == false, it's an infinite loop, therefore
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| 		//    the assertion and the error are unreachable.
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| 		assert(x > 0);
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| 	}
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| }
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| // ====
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| // SMTSolvers: z3
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