How to create a For Loop in a Solidity smart contract

A loop will run n times where n is the number we pass into the function. There should be an upper bound so it does not run out of gas.

uint public count
Function nameLoop(uint n) public {
         For(uint i =0; i < n; i++ ) {
	           Count +=1; //Execute this code in the brace. Increment the counter by 1 every time the for loop runs
          }

Try it in Remix

  • Local variable starts at 0
  • While i < n the code will get executed and for every pass we will increment i.
    • Let’s say we pass in 4. Then the function will run from 0-4 times
      • 0<4 – function executes in braces below statement, then increment i
      • 1<4 – function executes in braces below statement, then increment i
      • 2<4 – function executes in braces below statement, then increment i
      • 3<4– function executes in braces below statement, then increment i
      • 4 is not <4 so loop terminates

This code is for learning and entertainment purposes only. The code has not been audited and use at your own risk. Remember smart contracts are experimental and could contain bugs.

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