Forgotten measurements

input/code.cpp: In function 'int main()':
input/code.cpp:14:18: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |     for(ll i=0; i<s.size(); i++){
      |                 ~^~~~~~~~~

#include <iostream>
#include <string>
#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
int main(){
    ll idx1=0;
    ll idx2=0;

    string s;
    cin >> s;

    for(ll i=0; i<s.size(); i++){
        if(s[i]=='U') idx1 +=1;
        else if(s[i]=='D') idx1 -=1;
        else if(s[i]=='L') idx2 +=1;
        else if(s[i]=='R') idx2 -=1;
    }

    cout << abs(idx1) + abs(idx2) << endl;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: WRONG ANSWER

Test 3

Verdict: WRONG ANSWER

Test 4

Verdict: WRONG ANSWER

Test 5

Verdict: WRONG ANSWER

Test 6

Verdict: WRONG ANSWER

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: WRONG ANSWER

Test 9

Verdict: WRONG ANSWER

Test 10

Verdict: WRONG ANSWER

Test 11

Verdict: WRONG ANSWER