604 B
604 B
[[ a11 a12 ⋯ a1n | b_1] [ 0 (a22 - \frac{a_{}21}{a22}a11) ⋯ a2n | b_2 - \frac{a21}{a11}b_1 ]]
for (int i = 1; i < n; i++) {
float factor = -a[i][0] / a[0][0];
for (int j = 1; j < n; j++) {
a[i][j] = a[i][j] + factor * a[0][j];
}
b[i] = b[i] + factor * b[0];
}
for (int k = 0; k < (n - 1); k++) {
for (int i = k+1; i < n; i++) {
float factor = -a[i][k] / a[k][k];
for (int j = k+1; j < n; j++) {
a[i][j] = a[i][j] + factor * a[j][k];
}
b[i] = b[i] + factor*b[k];
}
}