Swapping letters

input/code.cpp: In function 'int main()':
input/code.cpp:35:14: warning: array subscript has type 'char' [-Wchar-subscripts]
         l0[c0].push_back(c1);
              ^
input/code.cpp:36:14: warning: array subscript has type 'char' [-Wchar-subscripts]
         l0[c1].push_back(c0);
              ^
input/code.cpp:56:29: warning: array subscript has type 'char' [-Wchar-subscripts]
         int j = find(y, at[c], c);
                             ^
input/code.cpp:57:13: warning: array subscript has type 'char' [-Wchar-subscripts]
         at[c] = j + 1;
             ^
input/code.cpp:59:26: warning: array subscript has type 'char' [-Wchar-subscripts]
         for (int r : l0[c]) {
                          ^
input/code.cpp:64:26: warning: array subscript has type 'char' [-Wchar-subscripts]
             for(a = pvy[c][r]; y[a] != c; a++)
                          ^
input/code.cpp:67:18: warning: array subscript has type 'char' [-Wchar-subscripts]
             pvy[c][r] = a + 1;...

#include <vector>
#include <iostream>
#include <string>

std::vector<int> l0[1000];
int at[123];
int prx[123];
int pry[123][123];
int pvy[123][123];

int find(const char* y, int a, char c) {
    int i = a;
    while(y[i] != c) i++;
    return i;
}

int main() {
    for(int i = 0; i < 123; i++)  {
        for(int j = 0; j < 123; j++)  {
            pvy[i][j] = 0;
            pry[i][j] = 0;
        }
    }

    int n;
    std::cin >> n;

    while (n > 0) {
        n -= 1;
        char c0;
        char c1;
        std::cin >> c0;
        std::cin >> c1;

        l0[c0].push_back(c1);
        l0[c1].push_back(c0);
    }

    std::string x0;
    std::string y0;

    std::cin >> x0;
    std::cin >> y0;

    int N = x0.size();

    const char* x = x0.c_str();
    const char* y = y0.c_str();

    int i = 0;
    for(int i = 0; i < N; i++) {
        if (i % 10000 == 9999)
            std::cout << i << " " << N << std::endl;

        char c = x[i];
        int j = find(y, at[c], c);
        at[c] = j + 1;

        for (int r : l0[c]) {
            int cx = prx[r];

            int n = 0;
            int a;
            for(a = pvy[c][r]; y[a] != c; a++) 
                if (y[a] == r) n++;

            pvy[c][r] = a + 1;
            pry[c][r] += n;
            int cy = pry[c][r];

            if (cx != cy) {
                std::cout << "NO" << std::endl;
                return 0;
            }
        }
        prx[c] += 1;
    }
    std::cout << "YES" << std::endl;
    return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: WRONG ANSWER

Test 5

Verdict: WRONG ANSWER

Test 6

Verdict: WRONG ANSWER

Test 7

Verdict: ACCEPTED

Test 8

Verdict: WRONG ANSWER

Test 9

Verdict: WRONG ANSWER

Test 10

Verdict: WRONG ANSWER