Steve Robinson

#include <stdio.h>
#include <stdlib.h>

struct MiniMatrix {
    int cols, rows;
    int vals[8][8];
};

int parsematrix(struct MiniMatrix* dest, char* filename) {
    int i, j;
    char end;
    FILE* in = fopen(filename, "r");

    if(in == NULL) {
        return 1;
    }

    fscanf(in, "%d,%d\n", &dest->cols, &dest->rows);

    for(i = 0; i < dest->rows; i++) {
        for(j = 0; j < dest->cols; j++) {
            fscanf(in, "%d%c", &dest->vals[i][j], &end);
        }
    }
    fclose(in);

    return 0;
}

int outputmatrix(struct MiniMatrix* src, char* filename) {
    int i, j;
    FILE* out = fopen(filename, "w");

    if(out == NULL) {
        return 1;
    }

    fprintf(out, "%d,%d\n", src->cols, src->rows);

    for(i = 0; i < src->rows; i++) {
        for(j = 0; j < src->cols; j++) {
            fprintf(out, "%d", src->vals[i][j]);

            if(j < src->cols-1) {
                fprintf(out, ",");
            }
        }
        fprintf(out, "\n");
    }

    fclose(out);

    return 0;
}

int multmatrix(struct MiniMatrix* c, struct MiniMatrix* a, struct MiniMatrix* b) {
    int i, j, k;

    if(a->cols != b->rows) {
        return 1;
    }

    c->cols = b->cols;
    c->rows = a->rows;

    for(i = 0; i < a->rows; i++) {
        for(j = 0; j < b->cols; j++) {
            c->vals[i][j] = 0;

            for(k = 0; k < a->cols; k++) {
                c->vals[i][j] += (int)((((long long)a->vals[i][k])*((long long)b->vals[k][j]))%10000000LL);
            }
        }
    }

    return 0;
}

int main() {
    struct MiniMatrix res1, res2, res3;

    parsematrix(&res1, "sunday.txt");
    parsematrix(&res3, "saturday.txt");
    multmatrix(&res2, &res1, &res3);
    parsematrix(&res3, "friday.txt");
    multmatrix(&res1, &res2, &res3);
    parsematrix(&res3, "thursday.txt");
    multmatrix(&res2, &res1, &res3);
    parsematrix(&res3, "wednesday.txt");
    multmatrix(&res1, &res2, &res3);
    parsematrix(&res3, "tuesday.txt");
    multmatrix(&res2, &res1, &res3);
    parsematrix(&res3, "monday.txt");
    multmatrix(&res1, &res2, &res3);

    multmatrix(&res2, &res1, &res1);
    multmatrix(&res3, &res2, &res2);
    multmatrix(&res2, &res3, &res3);
    multmatrix(&res3, &res2, &res2);
    multmatrix(&res2, &res3, &res1);

    parsematrix(&res3, "finalize.txt");
    multmatrix(&res1, &res2, &res3);

    outputmatrix(&res1, "result.txt");

    return 0;
}