int min = 0;
int myr = 0;
int temp[SIZE][SIZE];
int size = 0;
...//some initialization

omp_set_num_threads(1);
start_time = omp_get_wtime();
    #ifdef _OPENMP
    #pragma omp parallel for firstprivate(min, size) reduction(+:myr)
    #endif
    for(int i = 0; i < size; i++){
        min = INFINITY;
        for(int j = 0; j < size; j++){
                if (temp[i][j] < min)
                    min = temp[i][j];
        }
        myr+=min;
        for(int j = 0; j < size; j++)
                temp[i][j]-=min;
    }
end_time = omp_get_wtime();

int const size0 = size;
#ifdef _OPENMP
#pragma omp parallel for reduction(+:myr)
#endif
for(int i = 0; i < size0; i++){
    int min = INFINITY;
    int * tmp = temp[i];
    for(int j = 0; j < size0; j++){
            if (tmp[j] < min)
                min = tmp[j];
    }
    for(int j = 0; j < size0; j++)
            tmp[j]-=min;
    myr+=min;
}

#pragma omp parallel private(myr_private) shared(myr)
{
    myr_private = 0;
    #pragma omp for
    for(int i = 0; i < size; i++){
        int min = INFINITY;
        int * tmp = temp[i];
        for(int j = 0; j < size; j++){
            if (tmp[j] < min)
                min = tmp[j];
        }
        for(int j = 0; j < size; j++)
            tmp[j]-=min;
        myr_private+=min;
    }
    #pragma omp critical
    {
        myr+=myr_private;
    }
}