求助, 本题只拿了10分

//john11
#include <stdio.h>
#include <stdlib.h>
#include <math.h>

long long int readnum, codenum;
long long int min = 0x7fffffffffffffff;
int main(void)
{   
    long long int i, j;
    long long int lreadiss, lreadcode, lcode;
    long long int *codes, *readiss, *readcode;
    scanf("%lld %lld", &readnum, &codenum);
    codes = malloc(codenum * sizeof(long long int) + 1);
    for(i = 0; i < codenum; i++) {
        scanf("%lld", &codes[i]);
    }
    readiss = malloc(readnum * sizeof(long long int) + 1);
    readcode = malloc(readnum * sizeof(long long int) + 1);
    for(i = 0; i < readnum; i++) {
        scanf("%lld %lld", &readiss[i], &readcode[i]);
    }
    for(i = 0; i < readnum; i++) {
        lreadiss = readiss[i];
        lreadcode = readcode[i];
        for(j = 0; j < codenum; j++) {
            lcode = codes[j];
            if(lcode % (long long int)pow(10, lreadiss) == lreadcode) {
                if(lcode < min) {
                    min = lcode;
                }
            } else if(j == codenum-1) {
                if(min == 0x7fffffffffffffff) {
                    printf("-1\n");
                } else {
                    printf("%lld\n", min);
                    min = 0x7fffffffffffffff;
                }
            }
        }
    }
    free(codes);
    free(readiss);
    free(readcode);
    return 0;
}