#pragma GCC optimize ("O3")

#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <map>
#include <unordered_map>
#include <set>
#include <unordered_set>
#include <queue>
#include <set>
#include <algorithm>
#include <numeric>
#include <list>
using namespace std;

using QWORD  = uint64_t;
using SQWORD = int64_t;
using DWORD  = uint32_t;
using SDWORD = int32_t;
using WORD   = uint16_t;
using SWORD  = int16_t;
using BYTE   = uint8_t;
using SBYTE  = int8_t;
using DOUBLE = double;
using FLOAT  = float;

#define MIN_SDWORD (-2147483648)
#define MAX_SDWORD (2147483647)
#define MIN_SBYTE (-128)
#define MAX_SBYTE (127)

#define MIN_SQWORD (0x8000000000000000)
#define MAX_SQWORD (0x7FFFFFFFFFFFFFFF)

#define MAX_QWORD  (0xFFFFFFFFFFFFFFFF)
#define MAX_DWORD  (0xFFFFFFFF)
#define MAX_WORD   (0xFFFF)
#define MAX_BYTE   (0xFF)


#define ArrayLength(a)  (sizeof(a) / sizeof(a[0]))

static inline QWORD MAX(QWORD a, QWORD b) { return a > b ? a : b; }
static inline DWORD MAX(DWORD a, DWORD b) { return a > b ? a : b; }
static inline SDWORD MAX(SDWORD a, SDWORD b) { return a > b ? a : b; }
static inline QWORD MIN(QWORD a, QWORD b) { return a < b ? a : b; }
static inline DWORD MIN(DWORD a, DWORD b) { return a < b ? a : b; }
static inline SDWORD MIN(SDWORD a, SDWORD b) { return a < b ? a : b; }

static inline SDWORD DIV_UP_N(SDWORD a, SDWORD b) {return (a + b-1) / b;}
static inline SQWORD DIV_UP_N(SQWORD a, SQWORD b) {return (a + b-1) / b;}

#define BYTE_BITS   (8)
#define WORD_BITS   (16)
#define DWORD_BITS  (32)
#define QWORD_BITS  (64)

using M_BOOL = bool;
#define M_TRUE (true)
#define M_FALSE (false)
#define DIVISOR (1000000007)

static inline void inputString(char *pcStr)
{
    char *pcCur = pcStr;
    for (;;) {
        char c = getchar();
        if (('\n' == c) || (EOF == c)) {
            break;
        }
        *pcCur = c;
        pcCur++;
    }
    *pcCur = '\0';
}


static inline SQWORD inputSQWORD(void)
{
    SQWORD sqNumber = 0;
    SQWORD sqMultiplier = 1;
    M_BOOL bRead = M_FALSE;
    for (;;) {
        char c = getchar();
        if (!bRead) {
            if ('-' == c) {
                sqMultiplier = -1;
            }
        }
        if (('0' <= c) && (c <= '9')) {
            sqNumber *= 10LL;
            sqNumber += (SQWORD)(c - '0');
            bRead = M_TRUE;
        } else {
            if (bRead) {
                return sqNumber * sqMultiplier;
            }
        }
    }
}


static inline SDWORD inputSDWORD(void)
{
    SDWORD lNumber = 0;
    SDWORD lMultiplier = 1;
    M_BOOL bRead = M_FALSE;
    for (;;) {
        char c = getchar();
        if (!bRead) {
            if ('-' == c) {
                lMultiplier = -1;
            }
        }
        if (('0' <= c) && (c <= '9')) {
            lNumber *= 10;
            lNumber += (c - '0');
            bRead = M_TRUE;
        } else {
            if (bRead) {
                return lNumber * lMultiplier;
            }
        }
    }
}

static inline DOUBLE inputFP(void)
{
    DOUBLE dInt = 0.0;
    DOUBLE dFrac = 0.0;
    DOUBLE dMultiplier = 1.0;
    DWORD dwFpCnt = 0;
    DOUBLE *pdCur = &dInt;
    M_BOOL bRead = M_FALSE;
    for (;;) {
        char c = getchar();
        if (!bRead) {
            if ('-' == c) {
                dMultiplier = -1;
            }
        }
        if ('.' == c) {
            pdCur = &dFrac;
        } else if (('0' <= c) && (c <= '9')) {
            (*pdCur) *= 10;
            (*pdCur) += (DOUBLE)(c - '0');
            bRead = M_TRUE;
            if (pdCur == &dFrac) {
                dwFpCnt++;
            }
        } else {
            if (bRead) {
                return dMultiplier * (dInt + dFrac / (pow((DOUBLE)10.0 , (DOUBLE)dwFpCnt)));
            }
        }
    }
}


/**
 *  mod による操作ライブラリ
 */

#define ANS_MOD (1000000007LL)
 
static SQWORD addMod(SQWORD x, SQWORD y)
{ 
    return (x + y) % ANS_MOD;
}
 
static SQWORD subMod(SQWORD x, SQWORD y)
{
    return (x - y + ANS_MOD) % ANS_MOD;
}
 
static SQWORD mulMod(SQWORD x, SQWORD y) 
{
    return (x * y) % ANS_MOD;
}
 
static SQWORD powMod(SQWORD x, SQWORD e) {
    SQWORD v = 1;
    for (; e; x = mulMod(x, x), e >>= 1) {
        if (e & 1) {
            v = mulMod(v, x);
        }
    }
    return v;
}
 
static SQWORD divMod(SQWORD x, SQWORD y)
{
    return mulMod(x, powMod(y, ANS_MOD - 2));
}
 
 
static SQWORD combMod(SQWORD n, SQWORD k)
{
    SQWORD v=1;
    for(SQWORD i=1; i<=k; i++) {
        v = divMod(mulMod(v, n-i+1),i);
    } 
    return v;
}

/*----------------------------------------------*/

typedef struct {
    SQWORD sqA;
    SQWORD sqB;
    SQWORD sqCost;
} ST_ELEM;

int main(void)
{
    SQWORD sqInput_N = inputSQWORD();
    SQWORD sqInput_Ma = inputSQWORD();
    SQWORD sqInput_Mb = inputSQWORD();

    vector<ST_ELEM> vecElem;

    for (SDWORD lIdx = 0; lIdx < sqInput_N; lIdx++) {
        SQWORD sqInput_a = inputSQWORD();
        SQWORD sqInput_b = inputSQWORD();
        SQWORD sqInput_c = inputSQWORD();

        vecElem.emplace_back(ST_ELEM{ sqInput_a, sqInput_b, sqInput_c});
    }

    /*
    *   dp(i)[j][k]
    *   i番目までの薬を使ったとき A = j, B = k となるようなコストの最小値 
    *   dp(i)[j][k] = min(dp(i-1)[j-A_i][k-B_i] + C_i)
    */
#define MAX_N_ELEM  (40)
#define MAX_QTY     (10)
#define SIZE_DP     (MAX_N_ELEM * MAX_QTY + 1)
    static SQWORD s_asqDpTbl[SIZE_DP][SIZE_DP];
    for (SQWORD sqIdxI = 0; sqIdxI < SIZE_DP; sqIdxI++) {
        for (SQWORD sqIdxJ = 0; sqIdxJ < SIZE_DP; sqIdxJ++) {
            s_asqDpTbl[sqIdxI][sqIdxJ] = MAX_SDWORD;
        }
    }
    s_asqDpTbl[0][0] = 0;

    for (auto elem: vecElem) {
        for (SQWORD sqIdxA = SIZE_DP - 1; 0 <= sqIdxA; sqIdxA--) {
            for (SQWORD sqIdxB = SIZE_DP - 1; 0 <= sqIdxB; sqIdxB--) {
                if ((elem.sqA <= sqIdxA) && (elem.sqB <= sqIdxB)) {
                    s_asqDpTbl[sqIdxA][sqIdxB]
                        = min(s_asqDpTbl[sqIdxA][sqIdxB], 
                              s_asqDpTbl[sqIdxA - elem.sqA][sqIdxB - elem.sqB] + elem.sqCost);
                }
            }
        }
    }

    SQWORD sqMinCost = MAX_SDWORD;
    for (SQWORD sqIdx = 1; sqIdx <= MAX_N_ELEM; sqIdx++) {
        SQWORD sqQtyA = sqIdx * sqInput_Ma;
        SQWORD sqQtyB = sqIdx * sqInput_Mb;
        if ((sqQtyA < SIZE_DP) && (sqQtyB < SIZE_DP)) {
            sqMinCost = min(sqMinCost, s_asqDpTbl[sqQtyA][sqQtyB]);
        }
    }
    if (MAX_SDWORD == sqMinCost) {
        printf("-1");
    } else {
        printf("%lld\n", sqMinCost);
    }
    return 0;
}

Measured memory_bytes: 1536